bt_open.c
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上传日期:2022-05-23
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- /*-
- * See the file LICENSE for redistribution information.
- *
- * Copyright (c) 1996-2002
- * Sleepycat Software. All rights reserved.
- */
- /*
- * Copyright (c) 1990, 1993, 1994, 1995, 1996
- * Keith Bostic. All rights reserved.
- */
- /*
- * Copyright (c) 1990, 1993, 1994, 1995
- * The Regents of the University of California. All rights reserved.
- *
- * This code is derived from software contributed to Berkeley by
- * Mike Olson.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in the
- * documentation and/or other materials provided with the distribution.
- * 3. Neither the name of the University nor the names of its contributors
- * may be used to endorse or promote products derived from this software
- * without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
- * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
- * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
- * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
- */
- #include "db_config.h"
- #ifndef lint
- static const char revid[] = "$Id: bt_open.c,v 11.76 2002/09/04 19:06:42 margo Exp $";
- #endif /* not lint */
- #ifndef NO_SYSTEM_INCLUDES
- #include <sys/types.h>
- #include <limits.h>
- #include <string.h>
- #endif
- #include "db_int.h"
- #include "dbinc/crypto.h"
- #include "dbinc/db_page.h"
- #include "dbinc/db_swap.h"
- #include "dbinc/btree.h"
- #include "dbinc/db_shash.h"
- #include "dbinc/lock.h"
- #include "dbinc/log.h"
- #include "dbinc/fop.h"
- static void __bam_init_meta __P((DB *, BTMETA *, db_pgno_t, DB_LSN *));
- /*
- * __bam_open --
- * Open a btree.
- *
- * PUBLIC: int __bam_open __P((DB *,
- * PUBLIC: DB_TXN *, const char *, db_pgno_t, u_int32_t));
- */
- int
- __bam_open(dbp, txn, name, base_pgno, flags)
- DB *dbp;
- DB_TXN *txn;
- const char *name;
- db_pgno_t base_pgno;
- u_int32_t flags;
- {
- BTREE *t;
- COMPQUIET(name, NULL);
- t = dbp->bt_internal;
- /* Initialize the remaining fields/methods of the DB. */
- dbp->key_range = __bam_key_range;
- dbp->stat = __bam_stat;
- /*
- * We don't permit the user to specify a prefix routine if they didn't
- * also specify a comparison routine, they can't know enough about our
- * comparison routine to get it right.
- */
- if (t->bt_compare == __bam_defcmp && t->bt_prefix != __bam_defpfx) {
- __db_err(dbp->dbenv,
- "prefix comparison may not be specified for default comparison routine");
- return (EINVAL);
- }
- /*
- * Verify that the bt_minkey value specified won't cause the
- * calculation of ovflsize to underflow [#2406] for this pagesize.
- */
- if (B_MINKEY_TO_OVFLSIZE(dbp, t->bt_minkey, dbp->pgsize) >
- B_MINKEY_TO_OVFLSIZE(dbp, DEFMINKEYPAGE, dbp->pgsize)) {
- __db_err(dbp->dbenv,
- "bt_minkey value of %lu too high for page size of %lu",
- (u_long)t->bt_minkey, (u_long)dbp->pgsize);
- return (EINVAL);
- }
- /* Start up the tree. */
- return (__bam_read_root(dbp, txn, base_pgno, flags));
- }
- /*
- * __bam_metachk --
- *
- * PUBLIC: int __bam_metachk __P((DB *, const char *, BTMETA *));
- */
- int
- __bam_metachk(dbp, name, btm)
- DB *dbp;
- const char *name;
- BTMETA *btm;
- {
- DB_ENV *dbenv;
- u_int32_t vers;
- int ret;
- dbenv = dbp->dbenv;
- /*
- * At this point, all we know is that the magic number is for a Btree.
- * Check the version, the database may be out of date.
- */
- vers = btm->dbmeta.version;
- if (F_ISSET(dbp, DB_AM_SWAP))
- M_32_SWAP(vers);
- switch (vers) {
- case 6:
- case 7:
- __db_err(dbenv,
- "%s: btree version %lu requires a version upgrade",
- name, (u_long)vers);
- return (DB_OLD_VERSION);
- case 8:
- case 9:
- break;
- default:
- __db_err(dbenv,
- "%s: unsupported btree version: %lu", name, (u_long)vers);
- return (EINVAL);
- }
- /* Swap the page if we need to. */
- if (F_ISSET(dbp, DB_AM_SWAP) && (ret = __bam_mswap((PAGE *)btm)) != 0)
- return (ret);
- /*
- * Check application info against metadata info, and set info, flags,
- * and type based on metadata info.
- */
- if ((ret =
- __db_fchk(dbenv, "DB->open", btm->dbmeta.flags, BTM_MASK)) != 0)
- return (ret);
- if (F_ISSET(&btm->dbmeta, BTM_RECNO)) {
- if (dbp->type == DB_BTREE)
- goto wrong_type;
- dbp->type = DB_RECNO;
- DB_ILLEGAL_METHOD(dbp, DB_OK_RECNO);
- } else {
- if (dbp->type == DB_RECNO)
- goto wrong_type;
- dbp->type = DB_BTREE;
- DB_ILLEGAL_METHOD(dbp, DB_OK_BTREE);
- }
- if (F_ISSET(&btm->dbmeta, BTM_DUP))
- F_SET(dbp, DB_AM_DUP);
- else
- if (F_ISSET(dbp, DB_AM_DUP)) {
- __db_err(dbenv,
- "%s: DB_DUP specified to open method but not set in database",
- name);
- return (EINVAL);
- }
- if (F_ISSET(&btm->dbmeta, BTM_RECNUM)) {
- if (dbp->type != DB_BTREE)
- goto wrong_type;
- F_SET(dbp, DB_AM_RECNUM);
- if ((ret = __db_fcchk(dbenv,
- "DB->open", dbp->flags, DB_AM_DUP, DB_AM_RECNUM)) != 0)
- return (ret);
- } else
- if (F_ISSET(dbp, DB_AM_RECNUM)) {
- __db_err(dbenv,
- "%s: DB_RECNUM specified to open method but not set in database",
- name);
- return (EINVAL);
- }
- if (F_ISSET(&btm->dbmeta, BTM_FIXEDLEN)) {
- if (dbp->type != DB_RECNO)
- goto wrong_type;
- F_SET(dbp, DB_AM_FIXEDLEN);
- } else
- if (F_ISSET(dbp, DB_AM_FIXEDLEN)) {
- __db_err(dbenv,
- "%s: DB_FIXEDLEN specified to open method but not set in database",
- name);
- return (EINVAL);
- }
- if (F_ISSET(&btm->dbmeta, BTM_RENUMBER)) {
- if (dbp->type != DB_RECNO)
- goto wrong_type;
- F_SET(dbp, DB_AM_RENUMBER);
- } else
- if (F_ISSET(dbp, DB_AM_RENUMBER)) {
- __db_err(dbenv,
- "%s: DB_RENUMBER specified to open method but not set in database",
- name);
- return (EINVAL);
- }
- if (F_ISSET(&btm->dbmeta, BTM_SUBDB))
- F_SET(dbp, DB_AM_SUBDB);
- else
- if (F_ISSET(dbp, DB_AM_SUBDB)) {
- __db_err(dbenv,
- "%s: multiple databases specified but not supported by file",
- name);
- return (EINVAL);
- }
- if (F_ISSET(&btm->dbmeta, BTM_DUPSORT)) {
- if (dbp->dup_compare == NULL)
- dbp->dup_compare = __bam_defcmp;
- F_SET(dbp, DB_AM_DUPSORT);
- } else
- if (dbp->dup_compare != NULL) {
- __db_err(dbenv,
- "%s: duplicate sort specified but not supported in database",
- name);
- return (EINVAL);
- }
- /* Set the page size. */
- dbp->pgsize = btm->dbmeta.pagesize;
- /* Copy the file's ID. */
- memcpy(dbp->fileid, btm->dbmeta.uid, DB_FILE_ID_LEN);
- return (0);
- wrong_type:
- if (dbp->type == DB_BTREE)
- __db_err(dbenv,
- "open method type is Btree, database type is Recno");
- else
- __db_err(dbenv,
- "open method type is Recno, database type is Btree");
- return (EINVAL);
- }
- /*
- * __bam_read_root --
- * Read the root page and check a tree.
- *
- * PUBLIC: int __bam_read_root __P((DB *, DB_TXN *, db_pgno_t, u_int32_t));
- */
- int
- __bam_read_root(dbp, txn, base_pgno, flags)
- DB *dbp;
- DB_TXN *txn;
- db_pgno_t base_pgno;
- u_int32_t flags;
- {
- BTMETA *meta;
- BTREE *t;
- DBC *dbc;
- DB_LOCK metalock;
- DB_MPOOLFILE *mpf;
- int ret, t_ret;
- meta = NULL;
- t = dbp->bt_internal;
- LOCK_INIT(metalock);
- mpf = dbp->mpf;
- ret = 0;
- /* Get a cursor. */
- if ((ret = dbp->cursor(dbp, txn, &dbc, 0)) != 0)
- return (ret);
- /* Get the metadata page. */
- if ((ret =
- __db_lget(dbc, 0, base_pgno, DB_LOCK_READ, 0, &metalock)) != 0)
- goto err;
- if ((ret = mpf->get(mpf, &base_pgno, 0, (PAGE **)&meta)) != 0)
- goto err;
- /*
- * If the magic number is set, the tree has been created. Correct
- * any fields that may not be right. Note, all of the local flags
- * were set by DB->open.
- *
- * Otherwise, we'd better be in recovery or abort, in which case the
- * metadata page will be created/initialized elsewhere.
- */
- DB_ASSERT(meta->dbmeta.magic != 0 ||
- IS_RECOVERING(dbp->dbenv) || F_ISSET(dbp, DB_AM_RECOVER));
- t->bt_maxkey = meta->maxkey;
- t->bt_minkey = meta->minkey;
- t->re_pad = meta->re_pad;
- t->re_len = meta->re_len;
- t->bt_meta = base_pgno;
- t->bt_root = meta->root;
- /*
- * !!!
- * If creating a subdatabase, we've already done an insert when
- * we put the subdatabase's entry into the master database, so
- * our last-page-inserted value is wrongly initialized for the
- * master database, not the subdatabase we're creating. I'm not
- * sure where the *right* place to clear this value is, it's not
- * intuitively obvious that it belongs here.
- */
- t->bt_lpgno = PGNO_INVALID;
- /* We must initialize last_pgno, it could be stale. */
- if (!LF_ISSET(DB_RDONLY) && dbp->meta_pgno == PGNO_BASE_MD) {
- mpf->last_pgno(mpf, &meta->dbmeta.last_pgno);
- ret = mpf->put(mpf, meta, DB_MPOOL_DIRTY);
- } else
- ret = mpf->put(mpf, meta, 0);
- meta = NULL;
- err: /* Put the metadata page back. */
- if (meta != NULL && (t_ret = mpf->put(mpf, meta, 0)) != 0 && ret == 0)
- ret = t_ret;
- if ((t_ret = __LPUT(dbc, metalock)) != 0 && ret == 0)
- ret = t_ret;
- if ((t_ret = dbc->c_close(dbc)) != 0 && ret == 0)
- ret = t_ret;
- return (ret);
- }
- /*
- * __bam_init_meta --
- *
- * Initialize a btree meta-data page. The following fields may need
- * to be updated later: last_pgno, root.
- */
- static void
- __bam_init_meta(dbp, meta, pgno, lsnp)
- DB *dbp;
- BTMETA *meta;
- db_pgno_t pgno;
- DB_LSN *lsnp;
- {
- BTREE *t;
- memset(meta, 0, sizeof(BTMETA));
- meta->dbmeta.lsn = *lsnp;
- meta->dbmeta.pgno = pgno;
- meta->dbmeta.magic = DB_BTREEMAGIC;
- meta->dbmeta.version = DB_BTREEVERSION;
- meta->dbmeta.pagesize = dbp->pgsize;
- if (F_ISSET(dbp, DB_AM_CHKSUM))
- FLD_SET(meta->dbmeta.metaflags, DBMETA_CHKSUM);
- if (F_ISSET(dbp, DB_AM_ENCRYPT)) {
- meta->dbmeta.encrypt_alg =
- ((DB_CIPHER *)dbp->dbenv->crypto_handle)->alg;
- DB_ASSERT(meta->dbmeta.encrypt_alg != 0);
- meta->crypto_magic = meta->dbmeta.magic;
- }
- meta->dbmeta.type = P_BTREEMETA;
- meta->dbmeta.free = PGNO_INVALID;
- meta->dbmeta.last_pgno = pgno;
- if (F_ISSET(dbp, DB_AM_DUP))
- F_SET(&meta->dbmeta, BTM_DUP);
- if (F_ISSET(dbp, DB_AM_FIXEDLEN))
- F_SET(&meta->dbmeta, BTM_FIXEDLEN);
- if (F_ISSET(dbp, DB_AM_RECNUM))
- F_SET(&meta->dbmeta, BTM_RECNUM);
- if (F_ISSET(dbp, DB_AM_RENUMBER))
- F_SET(&meta->dbmeta, BTM_RENUMBER);
- if (F_ISSET(dbp, DB_AM_SUBDB))
- F_SET(&meta->dbmeta, BTM_SUBDB);
- if (dbp->dup_compare != NULL)
- F_SET(&meta->dbmeta, BTM_DUPSORT);
- if (dbp->type == DB_RECNO)
- F_SET(&meta->dbmeta, BTM_RECNO);
- memcpy(meta->dbmeta.uid, dbp->fileid, DB_FILE_ID_LEN);
- t = dbp->bt_internal;
- meta->maxkey = t->bt_maxkey;
- meta->minkey = t->bt_minkey;
- meta->re_len = t->re_len;
- meta->re_pad = t->re_pad;
- }
- /*
- * __bam_new_file --
- * Create the necessary pages to begin a new database file.
- *
- * This code appears more complex than it is because of the two cases (named
- * and unnamed). The way to read the code is that for each page being created,
- * there are three parts: 1) a "get page" chunk (which either uses malloc'd
- * memory or calls mpf->get), 2) the initialization, and 3) the "put page"
- * chunk which either does a fop write or an mpf->put.
- *
- * PUBLIC: int __bam_new_file __P((DB *, DB_TXN *, DB_FH *, const char *));
- */
- int
- __bam_new_file(dbp, txn, fhp, name)
- DB *dbp;
- DB_TXN *txn;
- DB_FH *fhp;
- const char *name;
- {
- BTMETA *meta;
- DB_ENV *dbenv;
- DB_LSN lsn;
- DB_MPOOLFILE *mpf;
- DB_PGINFO pginfo;
- DBT pdbt;
- PAGE *root;
- db_pgno_t pgno;
- int ret;
- void *buf;
- dbenv = dbp->dbenv;
- mpf = dbp->mpf;
- root = NULL;
- meta = NULL;
- memset(&pdbt, 0, sizeof(pdbt));
- /* Build meta-data page. */
- if (name == NULL) {
- pgno = PGNO_BASE_MD;
- ret = mpf->get(mpf, &pgno, DB_MPOOL_CREATE, &meta);
- } else {
- pginfo.db_pagesize = dbp->pgsize;
- pginfo.flags =
- F_ISSET(dbp, (DB_AM_CHKSUM | DB_AM_ENCRYPT | DB_AM_SWAP));
- pginfo.type = dbp->type;
- pdbt.data = &pginfo;
- pdbt.size = sizeof(pginfo);
- ret = __os_calloc(dbp->dbenv, 1, dbp->pgsize, &buf);
- meta = (BTMETA *)buf;
- }
- if (ret != 0)
- return (ret);
- LSN_NOT_LOGGED(lsn);
- __bam_init_meta(dbp, meta, PGNO_BASE_MD, &lsn);
- meta->root = 1;
- meta->dbmeta.last_pgno = 1;
- if (name == NULL)
- ret = mpf->put(mpf, meta, DB_MPOOL_DIRTY);
- else {
- if ((ret = __db_pgout(dbenv, PGNO_BASE_MD, meta, &pdbt)) != 0)
- goto err;
- ret = __fop_write(dbenv,
- txn, name, DB_APP_DATA, fhp, 0, buf, dbp->pgsize, 1);
- }
- if (ret != 0)
- goto err;
- meta = NULL;
- /* Now build root page. */
- if (name == NULL) {
- pgno = 1;
- if ((ret = mpf->get(mpf, &pgno, DB_MPOOL_CREATE, &root)) != 0)
- goto err;
- } else {
- #ifdef DIAGNOSTIC
- memset(buf, 0, dbp->pgsize);
- #endif
- root = (PAGE *)buf;
- }
- P_INIT(root, dbp->pgsize, 1, PGNO_INVALID, PGNO_INVALID,
- LEAFLEVEL, dbp->type == DB_RECNO ? P_LRECNO : P_LBTREE);
- LSN_NOT_LOGGED(root->lsn);
- if (name == NULL)
- ret = mpf->put(mpf, root, DB_MPOOL_DIRTY);
- else {
- if ((ret = __db_pgout(dbenv, root->pgno, root, &pdbt)) != 0)
- goto err;
- ret = __fop_write(dbenv, txn,
- name, DB_APP_DATA, fhp, dbp->pgsize, buf, dbp->pgsize, 1);
- }
- if (ret != 0)
- goto err;
- root = NULL;
- err: if (name != NULL)
- __os_free(dbenv, buf);
- else {
- if (meta != NULL)
- (void)mpf->put(mpf, meta, 0);
- if (root != NULL)
- (void)mpf->put(mpf, root, 0);
- }
- return (ret);
- }
- /*
- * __bam_new_subdb --
- * Create a metadata page and a root page for a new btree.
- *
- * PUBLIC: int __bam_new_subdb __P((DB *, DB *, DB_TXN *));
- */
- int
- __bam_new_subdb(mdbp, dbp, txn)
- DB *mdbp, *dbp;
- DB_TXN *txn;
- {
- BTMETA *meta;
- DBC *dbc;
- DB_ENV *dbenv;
- DB_LOCK metalock;
- DB_LSN lsn;
- DB_MPOOLFILE *mpf;
- PAGE *root;
- int ret, t_ret;
- dbenv = mdbp->dbenv;
- mpf = mdbp->mpf;
- dbc = NULL;
- meta = NULL;
- root = NULL;
- if ((ret = mdbp->cursor(mdbp, txn,
- &dbc, CDB_LOCKING(dbenv) ? DB_WRITECURSOR : 0)) != 0)
- return (ret);
- /* Get, and optionally create the metadata page. */
- if ((ret = __db_lget(dbc,
- 0, dbp->meta_pgno, DB_LOCK_WRITE, 0, &metalock)) != 0)
- goto err;
- if ((ret = mpf->get(mpf, &dbp->meta_pgno, DB_MPOOL_CREATE, &meta)) != 0)
- goto err;
- /* Build meta-data page. */
- lsn = meta->dbmeta.lsn;
- __bam_init_meta(dbp, meta, dbp->meta_pgno, &lsn);
- if ((ret = __db_log_page(mdbp,
- txn, &meta->dbmeta.lsn, dbp->meta_pgno, (PAGE *)meta)) != 0)
- goto err;
- /* Create and initialize a root page. */
- if ((ret = __db_new(dbc,
- dbp->type == DB_RECNO ? P_LRECNO : P_LBTREE, &root)) != 0)
- goto err;
- root->level = LEAFLEVEL;
- if (DBENV_LOGGING(dbenv) &&
- (ret = __bam_root_log(mdbp, txn, &meta->dbmeta.lsn, 0,
- meta->dbmeta.pgno, root->pgno, &meta->dbmeta.lsn)) != 0)
- goto err;
- meta->root = root->pgno;
- if ((ret =
- __db_log_page(mdbp, txn, &root->lsn, root->pgno, root)) != 0)
- goto err;
- /* Release the metadata and root pages. */
- if ((ret = mpf->put(mpf, meta, DB_MPOOL_DIRTY)) != 0)
- goto err;
- meta = NULL;
- if ((ret = mpf->put(mpf, root, DB_MPOOL_DIRTY)) != 0)
- goto err;
- root = NULL;
- err:
- if (meta != NULL)
- if ((t_ret = mpf->put(mpf, meta, 0)) != 0 && ret == 0)
- ret = t_ret;
- if (root != NULL)
- if ((t_ret = mpf->put(mpf, root, 0)) != 0 && ret == 0)
- ret = t_ret;
- if (LOCK_ISSET(metalock))
- if ((t_ret = __LPUT(dbc, metalock)) != 0 && ret == 0)
- ret = t_ret;
- if (dbc != NULL)
- if ((t_ret = dbc->c_close(dbc)) != 0 && ret == 0)
- ret = t_ret;
- return (ret);
- }