00001 /*- 00002 * See the file LICENSE for redistribution information. 00003 * 00004 * Copyright (c) 1996, 1997, 1998, 1999, 2000 00005 * Sleepycat Software. All rights reserved. 00006 */ 00007 /* 00008 * Copyright (c) 1995, 1996 00009 * The President and Fellows of Harvard University. All rights reserved. 00010 * 00011 * This code is derived from software contributed to Berkeley by 00012 * Margo Seltzer. 00013 * 00014 * Redistribution and use in source and binary forms, with or without 00015 * modification, are permitted provided that the following conditions 00016 * are met: 00017 * 1. Redistributions of source code must retain the above copyright 00018 * notice, this list of conditions and the following disclaimer. 00019 * 2. Redistributions in binary form must reproduce the above copyright 00020 * notice, this list of conditions and the following disclaimer in the 00021 * documentation and/or other materials provided with the distribution. 00022 * 3. Neither the name of the University nor the names of its contributors 00023 * may be used to endorse or promote products derived from this software 00024 * without specific prior written permission. 00025 * 00026 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 00027 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 00028 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 00029 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 00030 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 00031 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 00032 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 00033 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 00034 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 00035 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 00036 * SUCH DAMAGE. 00037 */ 00038 00039 #include "config.h" 00040 00041 #ifndef lint 00042 static const char revid[] = "$Id: db__dispatch_8c-source.html,v 1.1 2008年06月08日 10:17:25 sebdiaz Exp $"; 00043 #endif /* not lint */ 00044 00045 #ifndef NO_SYSTEM_INCLUDES 00046 #include <sys/types.h> 00047 00048 #include <errno.h> 00049 #include <stddef.h> 00050 #include <stdlib.h> 00051 #include <string.h> 00052 #endif 00053 00054 #include "db_int.h" 00055 #include "db_page.h" 00056 #include "db_dispatch.h" 00057 #include "db_am.h" 00058 #include "log_auto.h" 00059 #include "txn.h" 00060 #include "txn_auto.h" 00061 #include "log.h" 00062 00063 /* 00064 * CDB___db_dispatch -- 00065 * 00066 * This is the transaction dispatch function used by the db access methods. 00067 * It is designed to handle the record format used by all the access 00068 * methods (the one automatically generated by the db_{h,log,read}.sh 00069 * scripts in the tools directory). An application using a different 00070 * recovery paradigm will supply a different dispatch function to txn_open. 00071 * 00072 * PUBLIC: int CDB___db_dispatch __P((DB_ENV *, DBT *, DB_LSN *, db_recops, void *)); 00073 */ 00074 int 00075 CDB___db_dispatch(dbenv, db, lsnp, redo, info) 00076 DB_ENV *dbenv; /* The environment. */ 00077 DBT *db; /* The log record upon which to dispatch. */ 00078 DB_LSN *lsnp; /* The lsn of the record being dispatched. */ 00079 db_recops redo; /* Redo this op (or undo it). */ 00080 void *info; 00081 { 00082 u_int32_t rectype, txnid; 00083 00084 memcpy(&rectype, db->data, sizeof(rectype)); 00085 memcpy(&txnid, (u_int8_t *)db->data + sizeof(rectype), sizeof(txnid)); 00086 00087 switch (redo) { 00088 case DB_TXN_ABORT: 00089 return ((dbenv->dtab[rectype])(dbenv, db, lsnp, redo, info)); 00090 case DB_TXN_OPENFILES: 00091 if (rectype == DB_log_register) 00092 return (dbenv->dtab[rectype](dbenv, 00093 db, lsnp, redo, info)); 00094 break; 00095 case DB_TXN_BACKWARD_ROLL: 00096 /* 00097 * Running full recovery in the backward pass. If we've 00098 * seen this txnid before and added to it our commit list, 00099 * then we do nothing during this pass. If we've never 00100 * seen it, then we call the appropriate recovery routine 00101 * in "abort mode". 00102 * 00103 * We need to always undo DB_db_noop records, so that we 00104 * properly handle any aborts before the file was closed. 00105 */ 00106 if (rectype == DB_log_register || rectype == DB_txn_ckp || 00107 rectype == DB_db_noop || 00108 (CDB___db_txnlist_find(info, txnid) == DB_NOTFOUND && 00109 txnid != 0)) 00110 return (dbenv->dtab[rectype](dbenv, 00111 db, lsnp, DB_TXN_BACKWARD_ROLL, info)); 00112 break; 00113 case DB_TXN_FORWARD_ROLL: 00114 /* 00115 * In the forward pass, if we haven't seen the transaction, 00116 * do nothing, else recovery it. 00117 * 00118 * We need to always redo DB_db_noop records, so that we 00119 * properly handle any commits after the file was closed. 00120 */ 00121 if (rectype == DB_log_register || rectype == DB_txn_ckp || 00122 rectype == DB_db_noop || 00123 CDB___db_txnlist_find(info, txnid) != DB_NOTFOUND) 00124 return (dbenv->dtab[rectype](dbenv, 00125 db, lsnp, DB_TXN_FORWARD_ROLL, info)); 00126 break; 00127 default: 00128 return (CDB___db_unknown_flag(dbenv, "CDB___db_dispatch", redo)); 00129 } 00130 return (0); 00131 } 00132 00133 /* 00134 * CDB___db_add_recovery -- 00135 * 00136 * PUBLIC: int CDB___db_add_recovery __P((DB_ENV *, 00137 * PUBLIC: int (*)(DB_ENV *, DBT *, DB_LSN *, db_recops, void *), u_int32_t)); 00138 */ 00139 int 00140 CDB___db_add_recovery(dbenv, func, ndx) 00141 DB_ENV *dbenv; 00142 int (*func) __P((DB_ENV *, DBT *, DB_LSN *, db_recops, void *)); 00143 u_int32_t ndx; 00144 { 00145 u_int32_t i, nsize; 00146 int ret; 00147 00148 /* Check if we have to grow the table. */ 00149 if (ndx >= dbenv->dtab_size) { 00150 nsize = ndx + 40; 00151 if ((ret = CDB___os_realloc(dbenv, 00152 nsize * sizeof(dbenv->dtab[0]), NULL, &dbenv->dtab)) != 0) 00153 return (ret); 00154 for (i = dbenv->dtab_size; i < nsize; ++i) 00155 dbenv->dtab[i] = NULL; 00156 dbenv->dtab_size = nsize; 00157 } 00158 00159 dbenv->dtab[ndx] = func; 00160 return (0); 00161 } 00162 00163 /* 00164 * CDB___deprecated_recover -- 00165 * Stub routine for deprecated recovery functions. 00166 * 00167 * PUBLIC: int CDB___deprecated_recover 00168 * PUBLIC: __P((DB_ENV *, DBT *, DB_LSN *, db_recops, void *)); 00169 */ 00170 int 00171 CDB___deprecated_recover(dbenv, dbtp, lsnp, op, info) 00172 DB_ENV *dbenv; 00173 DBT *dbtp; 00174 DB_LSN *lsnp; 00175 db_recops op; 00176 void *info; 00177 { 00178 COMPQUIET(dbenv, NULL); 00179 COMPQUIET(dbtp, NULL); 00180 COMPQUIET(lsnp, NULL); 00181 COMPQUIET(op, 0); 00182 COMPQUIET(info, NULL); 00183 return (EINVAL); 00184 } 00185 00186 /* 00187 * CDB___db_txnlist_init -- 00188 * Initialize transaction linked list. 00189 * 00190 * PUBLIC: int CDB___db_txnlist_init __P((DB_ENV *, void *)); 00191 */ 00192 int 00193 CDB___db_txnlist_init(dbenv, retp) 00194 DB_ENV *dbenv; 00195 void *retp; 00196 { 00197 DB_TXNHEAD *headp; 00198 int ret; 00199 00200 if ((ret = CDB___os_malloc(dbenv, sizeof(DB_TXNHEAD), NULL, &headp)) != 0) 00201 return (ret); 00202 00203 LIST_INIT(&headp->head); 00204 headp->maxid = 0; 00205 headp->generation = 1; 00206 00207 *(void **)retp = headp; 00208 return (0); 00209 } 00210 00211 /* 00212 * CDB___db_txnlist_add -- 00213 * Add an element to our transaction linked list. 00214 * 00215 * PUBLIC: int CDB___db_txnlist_add __P((DB_ENV *, void *, u_int32_t)); 00216 */ 00217 int 00218 CDB___db_txnlist_add(dbenv, listp, txnid) 00219 DB_ENV *dbenv; 00220 void *listp; 00221 u_int32_t txnid; 00222 { 00223 DB_TXNHEAD *hp; 00224 DB_TXNLIST *elp; 00225 int ret; 00226 00227 if ((ret = CDB___os_malloc(dbenv, sizeof(DB_TXNLIST), NULL, &elp)) != 0) 00228 return (ret); 00229 00230 hp = (DB_TXNHEAD *)listp; 00231 LIST_INSERT_HEAD(&hp->head, elp, links); 00232 00233 elp->type = TXNLIST_TXNID; 00234 elp->u.t.txnid = txnid; 00235 if (txnid > hp->maxid) 00236 hp->maxid = txnid; 00237 elp->u.t.generation = hp->generation; 00238 00239 return (0); 00240 } 00241 00242 /* CDB___db_txnlist_close -- 00243 * 00244 * Call this when we close a file. It allows us to reconcile whether 00245 * we have done any operations on this file with whether the file appears 00246 * to have been deleted. If you never do any operations on a file, then 00247 * we assume it's OK to appear deleted. 00248 * 00249 * PUBLIC: int CDB___db_txnlist_close __P((void *, int32_t, u_int32_t)); 00250 */ 00251 00252 int 00253 CDB___db_txnlist_close(listp, lid, count) 00254 void *listp; 00255 int32_t lid; 00256 u_int32_t count; 00257 { 00258 DB_TXNHEAD *hp; 00259 DB_TXNLIST *p; 00260 00261 hp = (DB_TXNHEAD *)listp; 00262 for (p = LIST_FIRST(&hp->head); p != NULL; p = LIST_NEXT(p, links)) { 00263 if (p->type == TXNLIST_DELETE) 00264 if (lid == p->u.d.fileid && 00265 !F_ISSET(&p->u.d, TXNLIST_FLAG_CLOSED)) { 00266 p->u.d.count += count; 00267 return (0); 00268 } 00269 } 00270 00271 return (0); 00272 } 00273 00274 /* 00275 * CDB___db_txnlist_delete -- 00276 * 00277 * Record that a file was missing or deleted. If the deleted 00278 * flag is set, then we've encountered a delete of a file, else we've 00279 * just encountered a file that is missing. The lid is the log fileid 00280 * and is only meaningful if deleted is not equal to 0. 00281 * 00282 * PUBLIC: int CDB___db_txnlist_delete __P((DB_ENV *, 00283 * PUBLIC: void *, char *, u_int32_t, int)); 00284 */ 00285 int 00286 CDB___db_txnlist_delete(dbenv, listp, name, lid, deleted) 00287 DB_ENV *dbenv; 00288 void *listp; 00289 char *name; 00290 u_int32_t lid; 00291 int deleted; 00292 { 00293 DB_TXNHEAD *hp; 00294 DB_TXNLIST *p; 00295 int ret; 00296 00297 hp = (DB_TXNHEAD *)listp; 00298 for (p = LIST_FIRST(&hp->head); p != NULL; p = LIST_NEXT(p, links)) { 00299 if (p->type == TXNLIST_DELETE) 00300 if (strcmp(name, p->u.d.fname) == 0) { 00301 if (deleted) 00302 F_SET(&p->u.d, TXNLIST_FLAG_DELETED); 00303 else 00304 F_CLR(&p->u.d, TXNLIST_FLAG_CLOSED); 00305 return (0); 00306 } 00307 } 00308 00309 /* Need to add it. */ 00310 if ((ret = CDB___os_malloc(dbenv, sizeof(DB_TXNLIST), NULL, &p)) != 0) 00311 return (ret); 00312 LIST_INSERT_HEAD(&hp->head, p, links); 00313 00314 p->type = TXNLIST_DELETE; 00315 p->u.d.flags = 0; 00316 if (deleted) 00317 F_SET(&p->u.d, TXNLIST_FLAG_DELETED); 00318 p->u.d.fileid = lid; 00319 p->u.d.count = 0; 00320 ret = CDB___os_strdup(dbenv, name, &p->u.d.fname); 00321 00322 return (ret); 00323 } 00324 00325 /* 00326 * CDB___db_txnlist_end -- 00327 * Discard transaction linked list. Print out any error messages 00328 * for deleted files. 00329 * 00330 * PUBLIC: void CDB___db_txnlist_end __P((DB_ENV *, void *)); 00331 */ 00332 void 00333 CDB___db_txnlist_end(dbenv, listp) 00334 DB_ENV *dbenv; 00335 void *listp; 00336 { 00337 DB_TXNHEAD *hp; 00338 DB_TXNLIST *p; 00339 DB_LOG *lp; 00340 00341 hp = (DB_TXNHEAD *)listp; 00342 lp = (DB_LOG *)dbenv->lg_handle; 00343 while (hp != NULL && 00344 (p = LIST_FIRST(&hp->head)) != LIST_END(&hp->head)) { 00345 LIST_REMOVE(p, links); 00346 if (p->type == TXNLIST_DELETE) { 00347 /* 00348 * If we have a file that is not deleted and has 00349 * some operations, we flag the warning. Since 00350 * the file could still be open, we need to check 00351 * the actual log table as well. 00352 */ 00353 if ((!F_ISSET(&p->u.d, TXNLIST_FLAG_DELETED) && 00354 p->u.d.count != 0) || 00355 (!F_ISSET(&p->u.d, TXNLIST_FLAG_CLOSED) && 00356 p->u.d.fileid != (int32_t) TXNLIST_INVALID_ID && 00357 p->u.d.fileid < lp->dbentry_cnt && 00358 lp->dbentry[p->u.d.fileid].count != 0)) 00359 CDB___db_err(dbenv, "warning: %s: %s", 00360 p->u.d.fname, CDB_db_strerror(ENOENT)); 00361 CDB___os_freestr(p->u.d.fname); 00362 } 00363 CDB___os_free(p, sizeof(DB_TXNLIST)); 00364 } 00365 CDB___os_free(listp, sizeof(DB_TXNHEAD)); 00366 } 00367 00368 /* 00369 * CDB___db_txnlist_find -- 00370 * Checks to see if a txnid with the current generation is in the 00371 * txnid list. 00372 * 00373 * PUBLIC: int CDB___db_txnlist_find __P((void *, u_int32_t)); 00374 */ 00375 int 00376 CDB___db_txnlist_find(listp, txnid) 00377 void *listp; 00378 u_int32_t txnid; 00379 { 00380 DB_TXNHEAD *hp; 00381 DB_TXNLIST *p; 00382 00383 if (txnid == 0 || (hp = (DB_TXNHEAD *)listp) == NULL) 00384 return (DB_NOTFOUND); 00385 00386 for (p = LIST_FIRST(&hp->head); p != NULL; p = LIST_NEXT(p, links)) { 00387 if (p->type != TXNLIST_TXNID) 00388 continue; 00389 if (p->u.t.txnid == txnid && 00390 hp->generation == p->u.t.generation) { 00391 /* Move it to head of list. */ 00392 if (p != LIST_FIRST(&hp->head)) { 00393 LIST_REMOVE(p, links); 00394 LIST_INSERT_HEAD(&hp->head, p, links); 00395 } 00396 return (0); 00397 } 00398 } 00399 00400 return (DB_NOTFOUND); 00401 } 00402 00403 /* 00404 * CDB___db_txnlist_gen -- 00405 * Change the current generation number. 00406 * 00407 * PUBLIC: void CDB___db_txnlist_gen __P((void *, int)); 00408 */ 00409 void 00410 CDB___db_txnlist_gen(listp, incr) 00411 void *listp; 00412 int incr; 00413 { 00414 DB_TXNHEAD *hp; 00415 00416 /* 00417 * During recovery generation numbers keep track of how many "restart" 00418 * checkpoints we've seen. Restart checkpoints occur whenever we take 00419 * a checkpoint and there are no outstanding transactions. When that 00420 * happens, we can reset transaction IDs back to 1. It always happens 00421 * at recovery and it prevents us from exhausting the transaction IDs 00422 * name space. 00423 */ 00424 hp = (DB_TXNHEAD *)listp; 00425 hp->generation += incr; 00426 } 00427 00428 #ifdef DEBUG 00429 /* 00430 * CDB___db_txnlist_print -- 00431 * Print out the transaction list. 00432 * 00433 * PUBLIC: void CDB___db_txnlist_print __P((void *)); 00434 */ 00435 void 00436 CDB___db_txnlist_print(listp) 00437 void *listp; 00438 { 00439 DB_TXNHEAD *hp; 00440 DB_TXNLIST *p; 00441 00442 hp = (DB_TXNHEAD *)listp; 00443 00444 printf("Maxid: %lu Generation: %lu\n", 00445 (u_long)hp->maxid, (u_long)hp->generation); 00446 for (p = LIST_FIRST(&hp->head); p != NULL; p = LIST_NEXT(p, links)) { 00447 switch (p->type) { 00448 case TXNLIST_TXNID: 00449 printf("TXNID: %lu(%lu)\n", 00450 (u_long)p->u.t.txnid, (u_long)p->u.t.generation); 00451 break; 00452 case TXNLIST_DELETE: 00453 printf("FILE: %s id=%d ops=%d %s %s\n", 00454 p->u.d.fname, p->u.d.fileid, p->u.d.count, 00455 F_ISSET(&p->u.d, TXNLIST_FLAG_DELETED) ? 00456 "(deleted)" : "(missing)", 00457 F_ISSET(&p->u.d, TXNLIST_FLAG_CLOSED) ? 00458 "(closed)" : "(open)"); 00459 00460 break; 00461 default: 00462 printf("Unrecognized type: %d\n", p->type); 00463 break; 00464 } 00465 } 00466 } 00467 #endif