1/* 2 * Copyright (C) 2004-2009, 2012 Internet Systems Consortium, Inc. ("ISC") 3 * Copyright (C) 1999-2001 Internet Software Consortium. 4 * 5 * Permission to use, copy, modify, and/or distribute this software for any 6 * purpose with or without fee is hereby granted, provided that the above 7 * copyright notice and this permission notice appear in all copies. 8 * 9 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH 10 * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY 11 * AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT, 12 * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM 13 * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE 14 * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR 15 * PERFORMANCE OF THIS SOFTWARE. 16 */ 17 18/* $Id$ */ 19 20#ifndef DNS_JOURNAL_H 21#define DNS_JOURNAL_H 1 22 23/***** 24 ***** Module Info 25 *****/ 26 27/*! \file dns/journal.h 28 * \brief 29 * Database journaling. 30 */ 31 32/*** 33 *** Imports 34 ***/ 35 36#include <isc/lang.h> 37#include <isc/magic.h> 38 39#include <dns/name.h> 40#include <dns/diff.h> 41#include <dns/rdata.h> 42#include <dns/types.h> 43 44/*** 45 *** Defines. 46 ***/ 47#define DNS_JOURNALOPT_RESIGN 0x00000001 48 49/*** 50 *** Types 51 ***/ 52 53/*% 54 * A dns_journal_t represents an open journal file. This is an opaque type. 55 * 56 * A particular dns_journal_t object may be opened for writing, in which case 57 * it can be used for writing transactions to a journal file, or it can be 58 * opened for reading, in which case it can be used for reading transactions 59 * from (iterating over) a journal file. A single dns_journal_t object may 60 * not be used for both purposes. 61 */ 62typedef struct dns_journal dns_journal_t; 63 64 65/*** 66 *** Functions 67 ***/ 68 69ISC_LANG_BEGINDECLS 70 71/**************************************************************************/ 72 73isc_result_t 74dns_db_createsoatuple(dns_db_t *db, dns_dbversion_t *ver, isc_mem_t *mctx, 75 dns_diffop_t op, dns_difftuple_t **tp); 76/*!< brief 77 * Create a diff tuple for the current database SOA. 78 * XXX this probably belongs somewhere else. 79 */ 80 81 82/*@{*/ 83#define DNS_SERIAL_GT(a, b) ((int)(((a) - (b)) & 0xFFFFFFFF) > 0) 84#define DNS_SERIAL_GE(a, b) ((int)(((a) - (b)) & 0xFFFFFFFF) >= 0) 85/*!< brief 86 * Compare SOA serial numbers. DNS_SERIAL_GT(a, b) returns true iff 87 * a is "greater than" b where "greater than" is as defined in RFC1982. 88 * DNS_SERIAL_GE(a, b) returns true iff a is "greater than or equal to" b. 89 */ 90/*@}*/ 91 92/**************************************************************************/ 93/* 94 * Journal object creation and destruction. 95 */ 96 97isc_result_t 98dns_journal_open(isc_mem_t *mctx, const char *filename, isc_boolean_t write, 99 dns_journal_t **journalp); 100/*%< 101 * Open the journal file 'filename' and create a dns_journal_t object for it. 102 * 103 * If 'write' is ISC_TRUE, the journal is open for writing. If it does 104 * not exist, it is created. 105 * 106 * If 'write' is ISC_FALSE, the journal is open for reading. If it does 107 * not exist, ISC_R_NOTFOUND is returned. 108 */ 109 110void 111dns_journal_destroy(dns_journal_t **journalp); 112/*%< 113 * Destroy a dns_journal_t, closing any open files and freeing its memory. 114 */ 115 116/**************************************************************************/ 117/* 118 * Writing transactions to journals. 119 */ 120 121isc_result_t 122dns_journal_begin_transaction(dns_journal_t *j); 123/*%< 124 * Prepare to write a new transaction to the open journal file 'j'. 125 * 126 * Requires: 127 * \li 'j' is open for writing. 128 */ 129 130isc_result_t 131dns_journal_writediff(dns_journal_t *j, dns_diff_t *diff); 132/*%< 133 * Write 'diff' to the current transaction of journal file 'j'. 134 * 135 * Requires: 136 * \li 'j' is open for writing and dns_journal_begin_transaction() 137 * has been called. 138 * 139 *\li 'diff' is a full or partial, correctly ordered IXFR 140 * difference sequence. 141 */ 142 143isc_result_t 144dns_journal_commit(dns_journal_t *j); 145/*%< 146 * Commit the current transaction of journal file 'j'. 147 * 148 * Requires: 149 * \li 'j' is open for writing and dns_journal_begin_transaction() 150 * has been called. 151 * 152 * \li dns_journal_writediff() has been called one or more times 153 * to form a complete, correctly ordered IXFR difference 154 * sequence. 155 */ 156 157isc_result_t 158dns_journal_write_transaction(dns_journal_t *j, dns_diff_t *diff); 159/*% 160 * Write a complete transaction at once to a journal file, 161 * sorting it if necessary, and commit it. Equivalent to calling 162 * dns_diff_sort(), dns_journal_begin_transaction(), 163 * dns_journal_writediff(), and dns_journal_commit(). 164 * 165 * Requires: 166 *\li 'j' is open for writing. 167 * 168 * \li 'diff' contains exactly one SOA deletion, one SOA addition 169 * with a greater serial number, and possibly other changes, 170 * in arbitrary order. 171 */ 172 173/**************************************************************************/ 174/* 175 * Reading transactions from journals. 176 */ 177 178isc_uint32_t 179dns_journal_first_serial(dns_journal_t *j); 180isc_uint32_t 181dns_journal_last_serial(dns_journal_t *j); 182/*%< 183 * Get the first and last addressable serial number in the journal. 184 */ 185 186isc_result_t 187dns_journal_iter_init(dns_journal_t *j, 188 isc_uint32_t begin_serial, isc_uint32_t end_serial); 189/*%< 190 * Prepare to iterate over the transactions that will bring the database 191 * from SOA serial number 'begin_serial' to 'end_serial'. 192 * 193 * Returns: 194 *\li ISC_R_SUCCESS 195 *\li ISC_R_RANGE begin_serial is outside the addressable range. 196 *\li ISC_R_NOTFOUND begin_serial is within the range of addressable 197 * serial numbers covered by the journal, but 198 * this particular serial number does not exist. 199 */ 200 201/*@{*/ 202isc_result_t 203dns_journal_first_rr(dns_journal_t *j); 204isc_result_t 205dns_journal_next_rr(dns_journal_t *j); 206/*%< 207 * Position the iterator at the first/next RR in a journal 208 * transaction sequence established using dns_journal_iter_init(). 209 * 210 * Requires: 211 * \li dns_journal_iter_init() has been called. 212 * 213 */ 214/*@}*/ 215 216void 217dns_journal_current_rr(dns_journal_t *j, dns_name_t **name, isc_uint32_t *ttl, 218 dns_rdata_t **rdata); 219/*%< 220 * Get the name, ttl, and rdata of the current journal RR. 221 * 222 * Requires: 223 * \li The last call to dns_journal_first_rr() or dns_journal_next_rr() 224 * returned ISC_R_SUCCESS. 225 */ 226 227/**************************************************************************/ 228/* 229 * Database roll-forward. 230 */ 231 232isc_result_t 233dns_journal_rollforward(isc_mem_t *mctx, dns_db_t *db, unsigned int options, 234 const char *filename); 235 236isc_result_t 237dns_journal_rollforward2(isc_mem_t *mctx, dns_db_t *db, unsigned int options, 238 isc_uint32_t resign, const char *filename); 239/*%< 240 * Roll forward (play back) the journal file "filename" into the 241 * database "db". This should be called when the server starts 242 * after a shutdown or crash. 'resign' is how many seconds before 243 * a RRSIG is due to expire it should be scheduled to be regenerated. 244 * 245 * Requires: 246 *\li dns_journal_rollforward() requires that DNS_JOURNALOPT_RESIGN 247 * is not set. 248 *\li 'mctx' is a valid memory context. 249 *\li 'db' is a valid database which does not have a version 250 * open for writing. 251 *\li 'filename' is the name of the journal file belonging to 'db'. 252 * 253 * Returns: 254 *\li DNS_R_NOJOURNAL when journal does not exist. 255 *\li ISC_R_NOTFOUND when current serial in not in journal. 256 *\li ISC_R_RANGE when current serial in not in journals range. 257 *\li ISC_R_SUCCESS journal has been applied successfully to database. 258 * others 259 */ 260 261isc_result_t 262dns_journal_print(isc_mem_t *mctx, const char *filename, FILE *file); 263/* For debugging not general use */ 264 265isc_result_t 266dns_db_diff(isc_mem_t *mctx, 267 dns_db_t *dba, dns_dbversion_t *dbvera, 268 dns_db_t *dbb, dns_dbversion_t *dbverb, 269 const char *journal_filename); 270/*%< 271 * Compare the databases 'dba' and 'dbb' and generate a journal 272 * entry containing the changes to make 'dba' from 'dbb' (note 273 * the order). This journal entry will consist of a single, 274 * possibly very large transaction. Append the journal 275 * entry to the journal file specified by 'journal_filename'. 276 */ 277 278isc_result_t 279dns_journal_compact(isc_mem_t *mctx, char *filename, isc_uint32_t serial, 280 isc_uint32_t target_size); 281/*%< 282 * Attempt to compact the journal if it is greater that 'target_size'. 283 * Changes from 'serial' onwards will be preserved. If the journal 284 * exists and is non-empty 'serial' must exist in the journal. 285 */ 286 287ISC_LANG_ENDDECLS 288 289#endif /* DNS_JOURNAL_H */ 290