hash_dup.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
- * The Regents of the University of California. All rights reserved.
- *
- * This code is derived from software contributed to Berkeley by
- * Margo Seltzer.
- *
- * 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: hash_dup.c,v 11.76 2002/08/06 05:34:40 bostic Exp $";
- #endif /* not lint */
- /*
- * PACKAGE: hashing
- *
- * DESCRIPTION:
- * Manipulation of duplicates for the hash package.
- */
- #ifndef NO_SYSTEM_INCLUDES
- #include <sys/types.h>
- #include <string.h>
- #endif
- #include "db_int.h"
- #include "dbinc/db_page.h"
- #include "dbinc/hash.h"
- #include "dbinc/btree.h"
- static int __ham_c_chgpg __P((DBC *,
- db_pgno_t, u_int32_t, db_pgno_t, u_int32_t));
- static int __ham_check_move __P((DBC *, u_int32_t));
- static int __ham_dcursor __P((DBC *, db_pgno_t, u_int32_t));
- static int __ham_move_offpage __P((DBC *, PAGE *, u_int32_t, db_pgno_t));
- /*
- * Called from hash_access to add a duplicate key. nval is the new
- * value that we want to add. The flags correspond to the flag values
- * to cursor_put indicating where to add the new element.
- * There are 4 cases.
- * Case 1: The existing duplicate set already resides on a separate page.
- * We return and let the common code handle this.
- * Case 2: The element is small enough to just be added to the existing set.
- * Case 3: The element is large enough to be a big item, so we're going to
- * have to push the set onto a new page.
- * Case 4: The element is large enough to push the duplicate set onto a
- * separate page.
- *
- * PUBLIC: int __ham_add_dup __P((DBC *, DBT *, u_int32_t, db_pgno_t *));
- */
- int
- __ham_add_dup(dbc, nval, flags, pgnop)
- DBC *dbc;
- DBT *nval;
- u_int32_t flags;
- db_pgno_t *pgnop;
- {
- DB *dbp;
- DBT pval, tmp_val;
- DB_MPOOLFILE *mpf;
- HASH_CURSOR *hcp;
- u_int32_t add_bytes, new_size;
- int cmp, ret;
- u_int8_t *hk;
- dbp = dbc->dbp;
- mpf = dbp->mpf;
- hcp = (HASH_CURSOR *)dbc->internal;
- DB_ASSERT(flags != DB_CURRENT);
- add_bytes = nval->size +
- (F_ISSET(nval, DB_DBT_PARTIAL) ? nval->doff : 0);
- add_bytes = DUP_SIZE(add_bytes);
- if ((ret = __ham_check_move(dbc, add_bytes)) != 0)
- return (ret);
- /*
- * Check if resulting duplicate set is going to need to go
- * onto a separate duplicate page. If so, convert the
- * duplicate set and add the new one. After conversion,
- * hcp->dndx is the first free ndx or the index of the
- * current pointer into the duplicate set.
- */
- hk = H_PAIRDATA(dbp, hcp->page, hcp->indx);
- /* Add the len bytes to the current singleton. */
- if (HPAGE_PTYPE(hk) != H_DUPLICATE)
- add_bytes += DUP_SIZE(0);
- new_size =
- LEN_HKEYDATA(dbp, hcp->page, dbp->pgsize, H_DATAINDEX(hcp->indx)) +
- add_bytes;
- /*
- * We convert to off-page duplicates if the item is a big item,
- * the addition of the new item will make the set large, or
- * if there isn't enough room on this page to add the next item.
- */
- if (HPAGE_PTYPE(hk) != H_OFFDUP &&
- (HPAGE_PTYPE(hk) == H_OFFPAGE || ISBIG(hcp, new_size) ||
- add_bytes > P_FREESPACE(dbp, hcp->page))) {
- if ((ret = __ham_dup_convert(dbc)) != 0)
- return (ret);
- return (hcp->opd->c_am_put(hcp->opd,
- NULL, nval, flags, NULL));
- }
- /* There are two separate cases here: on page and off page. */
- if (HPAGE_PTYPE(hk) != H_OFFDUP) {
- if (HPAGE_PTYPE(hk) != H_DUPLICATE) {
- pval.flags = 0;
- pval.data = HKEYDATA_DATA(hk);
- pval.size = LEN_HDATA(dbp, hcp->page, dbp->pgsize,
- hcp->indx);
- if ((ret = __ham_make_dup(dbp->dbenv,
- &pval, &tmp_val, &dbc->my_rdata.data,
- &dbc->my_rdata.ulen)) != 0 || (ret =
- __ham_replpair(dbc, &tmp_val, 1)) != 0)
- return (ret);
- hk = H_PAIRDATA(dbp, hcp->page, hcp->indx);
- HPAGE_PTYPE(hk) = H_DUPLICATE;
- /*
- * Update the cursor position since we now are in
- * duplicates.
- */
- F_SET(hcp, H_ISDUP);
- hcp->dup_off = 0;
- hcp->dup_len = pval.size;
- hcp->dup_tlen = DUP_SIZE(hcp->dup_len);
- }
- /* Now make the new entry a duplicate. */
- if ((ret = __ham_make_dup(dbp->dbenv, nval,
- &tmp_val, &dbc->my_rdata.data, &dbc->my_rdata.ulen)) != 0)
- return (ret);
- tmp_val.dlen = 0;
- switch (flags) { /* On page. */
- case DB_KEYFIRST:
- case DB_KEYLAST:
- case DB_NODUPDATA:
- if (dbp->dup_compare != NULL) {
- __ham_dsearch(dbc,
- nval, &tmp_val.doff, &cmp, flags);
- /* dup dups are not supported w/ sorted dups */
- if (cmp == 0)
- return (__db_duperr(dbp, flags));
- } else {
- hcp->dup_tlen = LEN_HDATA(dbp, hcp->page,
- dbp->pgsize, hcp->indx);
- hcp->dup_len = nval->size;
- F_SET(hcp, H_ISDUP);
- if (flags == DB_KEYFIRST)
- hcp->dup_off = tmp_val.doff = 0;
- else
- hcp->dup_off =
- tmp_val.doff = hcp->dup_tlen;
- }
- break;
- case DB_BEFORE:
- tmp_val.doff = hcp->dup_off;
- break;
- case DB_AFTER:
- tmp_val.doff = hcp->dup_off + DUP_SIZE(hcp->dup_len);
- break;
- }
- /* Add the duplicate. */
- ret = __ham_replpair(dbc, &tmp_val, 0);
- if (ret == 0)
- ret = mpf->set(mpf, hcp->page, DB_MPOOL_DIRTY);
- if (ret != 0)
- return (ret);
- /* Now, update the cursor if necessary. */
- switch (flags) {
- case DB_AFTER:
- hcp->dup_off += DUP_SIZE(hcp->dup_len);
- hcp->dup_len = nval->size;
- hcp->dup_tlen += (db_indx_t)DUP_SIZE(nval->size);
- break;
- case DB_KEYFIRST:
- case DB_KEYLAST:
- case DB_BEFORE:
- hcp->dup_tlen += (db_indx_t)DUP_SIZE(nval->size);
- hcp->dup_len = nval->size;
- break;
- }
- ret = __ham_c_update(dbc, tmp_val.size, 1, 1);
- return (ret);
- }
- /*
- * If we get here, then we're on duplicate pages; set pgnop and
- * return so the common code can handle it.
- */
- memcpy(pgnop, HOFFDUP_PGNO(H_PAIRDATA(dbp, hcp->page, hcp->indx)),
- sizeof(db_pgno_t));
- return (ret);
- }
- /*
- * Convert an on-page set of duplicates to an offpage set of duplicates.
- *
- * PUBLIC: int __ham_dup_convert __P((DBC *));
- */
- int
- __ham_dup_convert(dbc)
- DBC *dbc;
- {
- BOVERFLOW bo;
- DB *dbp;
- DBC **hcs;
- DBT dbt;
- DB_LSN lsn;
- DB_MPOOLFILE *mpf;
- HASH_CURSOR *hcp;
- HOFFPAGE ho;
- PAGE *dp;
- db_indx_t i, len, off;
- int c, ret, t_ret;
- u_int8_t *p, *pend;
- dbp = dbc->dbp;
- mpf = dbp->mpf;
- hcp = (HASH_CURSOR *)dbc->internal;
- /*
- * Create a new page for the duplicates.
- */
- if ((ret = __db_new(dbc,
- dbp->dup_compare == NULL ? P_LRECNO : P_LDUP, &dp)) != 0)
- return (ret);
- P_INIT(dp, dbp->pgsize,
- dp->pgno, PGNO_INVALID, PGNO_INVALID, LEAFLEVEL, TYPE(dp));
- /*
- * Get the list of cursors that may need to be updated.
- */
- if ((ret = __ham_get_clist(dbp,
- PGNO(hcp->page), (u_int32_t)hcp->indx, &hcs)) != 0)
- goto err;
- /*
- * Now put the duplicates onto the new page.
- */
- dbt.flags = 0;
- switch (HPAGE_PTYPE(H_PAIRDATA(dbp, hcp->page, hcp->indx))) {
- case H_KEYDATA:
- /* Simple case, one key on page; move it to dup page. */
- dbt.size = LEN_HDATA(dbp, hcp->page, dbp->pgsize, hcp->indx);
- dbt.data = HKEYDATA_DATA(H_PAIRDATA(dbp, hcp->page, hcp->indx));
- ret = __db_pitem(dbc,
- dp, 0, BKEYDATA_SIZE(dbt.size), NULL, &dbt);
- goto finish;
- case H_OFFPAGE:
- /* Simple case, one key on page; move it to dup page. */
- memcpy(&ho, P_ENTRY(dbp, hcp->page, H_DATAINDEX(hcp->indx)),
- HOFFPAGE_SIZE);
- UMRW_SET(bo.unused1);
- B_TSET(bo.type, ho.type, 0);
- UMRW_SET(bo.unused2);
- bo.pgno = ho.pgno;
- bo.tlen = ho.tlen;
- dbt.size = BOVERFLOW_SIZE;
- dbt.data = &bo;
- ret = __db_pitem(dbc, dp, 0, dbt.size, &dbt, NULL);
- finish: if (ret == 0) {
- if ((ret = mpf->set(mpf, dp, DB_MPOOL_DIRTY)) != 0)
- break;
- /* Update any other cursors. */
- if (hcs != NULL && DBC_LOGGING(dbc) &&
- IS_SUBTRANSACTION(dbc->txn)) {
- if ((ret = __ham_chgpg_log(dbp, dbc->txn,
- &lsn, 0, DB_HAM_DUP, PGNO(hcp->page),
- PGNO(dp), hcp->indx, 0)) != 0)
- break;
- }
- for (c = 0; hcs != NULL && hcs[c] != NULL; c++)
- if ((ret = __ham_dcursor(hcs[c],
- PGNO(dp), 0)) != 0)
- break;
- }
- break;
- case H_DUPLICATE:
- p = HKEYDATA_DATA(H_PAIRDATA(dbp, hcp->page, hcp->indx));
- pend = p +
- LEN_HDATA(dbp, hcp->page, dbp->pgsize, hcp->indx);
- /*
- * We need to maintain the duplicate cursor position.
- * Keep track of where we are in the duplicate set via
- * the offset, and when it matches the one in the cursor,
- * set the off-page duplicate cursor index to the current
- * index.
- */
- for (off = 0, i = 0; p < pend; i++) {
- memcpy(&len, p, sizeof(db_indx_t));
- dbt.size = len;
- p += sizeof(db_indx_t);
- dbt.data = p;
- p += len + sizeof(db_indx_t);
- if ((ret = __db_pitem(dbc, dp,
- i, BKEYDATA_SIZE(dbt.size), NULL, &dbt)) != 0)
- break;
- /* Update any other cursors */
- if (hcs != NULL && DBC_LOGGING(dbc) &&
- IS_SUBTRANSACTION(dbc->txn)) {
- if ((ret = __ham_chgpg_log(dbp, dbc->txn,
- &lsn, 0, DB_HAM_DUP, PGNO(hcp->page),
- PGNO(dp), hcp->indx, i)) != 0)
- break;
- }
- for (c = 0; hcs != NULL && hcs[c] != NULL; c++)
- if (((HASH_CURSOR *)(hcs[c]->internal))->dup_off
- == off && (ret = __ham_dcursor(hcs[c],
- PGNO(dp), i)) != 0)
- goto err;
- off += len + 2 * sizeof(db_indx_t);
- }
- break;
- default:
- ret = __db_pgfmt(dbp->dbenv, (u_long)hcp->pgno);
- break;
- }
- /*
- * Now attach this to the source page in place of the old duplicate
- * item.
- */
- if (ret == 0)
- ret = __ham_move_offpage(dbc, hcp->page,
- (u_int32_t)H_DATAINDEX(hcp->indx), PGNO(dp));
- err: if (ret == 0)
- ret = mpf->set(mpf, hcp->page, DB_MPOOL_DIRTY);
- if ((t_ret =
- mpf->put(mpf, dp, ret == 0 ? DB_MPOOL_DIRTY : 0)) != 0 && ret == 0)
- ret = t_ret;
- if (ret == 0)
- hcp->dup_tlen = hcp->dup_off = hcp->dup_len = 0;
- if (hcs != NULL)
- __os_free(dbp->dbenv, hcs);
- return (ret);
- }
- /*
- * __ham_make_dup
- *
- * Take a regular dbt and make it into a duplicate item with all the partial
- * information set appropriately. If the incoming dbt is a partial, assume
- * we are creating a new entry and make sure that we do any initial padding.
- *
- * PUBLIC: int __ham_make_dup __P((DB_ENV *,
- * PUBLIC: const DBT *, DBT *d, void **, u_int32_t *));
- */
- int
- __ham_make_dup(dbenv, notdup, duplicate, bufp, sizep)
- DB_ENV *dbenv;
- const DBT *notdup;
- DBT *duplicate;
- void **bufp;
- u_int32_t *sizep;
- {
- db_indx_t tsize, item_size;
- int ret;
- u_int8_t *p;
- item_size = (db_indx_t)notdup->size;
- if (F_ISSET(notdup, DB_DBT_PARTIAL))
- item_size += notdup->doff;
- tsize = DUP_SIZE(item_size);
- if ((ret = __ham_init_dbt(dbenv, duplicate, tsize, bufp, sizep)) != 0)
- return (ret);
- duplicate->dlen = 0;
- duplicate->flags = notdup->flags;
- F_SET(duplicate, DB_DBT_PARTIAL);
- p = duplicate->data;
- memcpy(p, &item_size, sizeof(db_indx_t));
- p += sizeof(db_indx_t);
- if (F_ISSET(notdup, DB_DBT_PARTIAL)) {
- memset(p, 0, notdup->doff);
- p += notdup->doff;
- }
- memcpy(p, notdup->data, notdup->size);
- p += notdup->size;
- memcpy(p, &item_size, sizeof(db_indx_t));
- duplicate->doff = 0;
- duplicate->dlen = notdup->size;
- return (0);
- }
- /*
- * __ham_check_move --
- *
- * Check if we can do whatever we need to on this page. If not,
- * then we'll have to move the current element to a new page.
- */
- static int
- __ham_check_move(dbc, add_len)
- DBC *dbc;
- u_int32_t add_len;
- {
- DB *dbp;
- DBT k, d;
- DB_LSN new_lsn;
- DB_MPOOLFILE *mpf;
- HASH_CURSOR *hcp;
- PAGE *next_pagep;
- db_pgno_t next_pgno;
- u_int32_t new_datalen, old_len, rectype;
- u_int8_t *hk;
- int ret;
- dbp = dbc->dbp;
- mpf = dbp->mpf;
- hcp = (HASH_CURSOR *)dbc->internal;
- hk = H_PAIRDATA(dbp, hcp->page, hcp->indx);
- /*
- * If the item is already off page duplicates or an offpage item,
- * then we know we can do whatever we need to do in-place
- */
- if (HPAGE_PTYPE(hk) == H_OFFDUP || HPAGE_PTYPE(hk) == H_OFFPAGE)
- return (0);
- old_len = LEN_HITEM(dbp, hcp->page, dbp->pgsize, H_DATAINDEX(hcp->indx));
- new_datalen = old_len - HKEYDATA_SIZE(0) + add_len;
- if (HPAGE_PTYPE(hk) != H_DUPLICATE)
- new_datalen += DUP_SIZE(0);
- /*
- * We need to add a new page under two conditions:
- * 1. The addition makes the total data length cross the BIG
- * threshold and the OFFDUP structure won't fit on this page.
- * 2. The addition does not make the total data cross the
- * threshold, but the new data won't fit on the page.
- * If neither of these is true, then we can return.
- */
- if (ISBIG(hcp, new_datalen) && (old_len > HOFFDUP_SIZE ||
- HOFFDUP_SIZE - old_len <= P_FREESPACE(dbp, hcp->page)))
- return (0);
- if (!ISBIG(hcp, new_datalen) && add_len <= P_FREESPACE(dbp, hcp->page))
- return (0);
- /*
- * If we get here, then we need to move the item to a new page.
- * Check if there are more pages in the chain. We now need to
- * update new_datalen to include the size of both the key and
- * the data that we need to move.
- */
- new_datalen = ISBIG(hcp, new_datalen) ?
- HOFFDUP_SIZE : HKEYDATA_SIZE(new_datalen);
- new_datalen += LEN_HITEM(dbp, hcp->page, dbp->pgsize, H_KEYINDEX(hcp->indx));
- next_pagep = NULL;
- for (next_pgno = NEXT_PGNO(hcp->page); next_pgno != PGNO_INVALID;
- next_pgno = NEXT_PGNO(next_pagep)) {
- if (next_pagep != NULL &&
- (ret = mpf->put(mpf, next_pagep, 0)) != 0)
- return (ret);
- if ((ret = mpf->get(mpf,
- &next_pgno, DB_MPOOL_CREATE, &next_pagep)) != 0)
- return (ret);
- if (P_FREESPACE(dbp, next_pagep) >= new_datalen)
- break;
- }
- /* No more pages, add one. */
- if (next_pagep == NULL && (ret = __ham_add_ovflpage(dbc,
- hcp->page, 0, &next_pagep)) != 0)
- return (ret);
- /* Add new page at the end of the chain. */
- if (P_FREESPACE(dbp, next_pagep) < new_datalen && (ret =
- __ham_add_ovflpage(dbc, next_pagep, 1, &next_pagep)) != 0) {
- (void)mpf->put(mpf, next_pagep, 0);
- return (ret);
- }
- /* Copy the item to the new page. */
- if (DBC_LOGGING(dbc)) {
- rectype = PUTPAIR;
- k.flags = 0;
- d.flags = 0;
- if (HPAGE_PTYPE(
- H_PAIRKEY(dbp, hcp->page, hcp->indx)) == H_OFFPAGE) {
- rectype |= PAIR_KEYMASK;
- k.data = H_PAIRKEY(dbp, hcp->page, hcp->indx);
- k.size = HOFFPAGE_SIZE;
- } else {
- k.data =
- HKEYDATA_DATA(H_PAIRKEY(dbp, hcp->page, hcp->indx));
- k.size =
- LEN_HKEY(dbp, hcp->page, dbp->pgsize, hcp->indx);
- }
- if (HPAGE_PTYPE(hk) == H_OFFPAGE) {
- rectype |= PAIR_DATAMASK;
- d.data = H_PAIRDATA(dbp, hcp->page, hcp->indx);
- d.size = HOFFPAGE_SIZE;
- } else {
- if (HPAGE_PTYPE(H_PAIRDATA(dbp, hcp->page, hcp->indx))
- == H_DUPLICATE)
- rectype |= PAIR_DUPMASK;
- d.data =
- HKEYDATA_DATA(H_PAIRDATA(dbp, hcp->page, hcp->indx));
- d.size = LEN_HDATA(dbp, hcp->page,
- dbp->pgsize, hcp->indx);
- }
- if ((ret = __ham_insdel_log(dbp,
- dbc->txn, &new_lsn, 0, rectype, PGNO(next_pagep),
- (u_int32_t)NUM_ENT(next_pagep), &LSN(next_pagep),
- &k, &d)) != 0) {
- (void)mpf->put(mpf, next_pagep, 0);
- return (ret);
- }
- } else
- LSN_NOT_LOGGED(new_lsn);
- /* Move lsn onto page. */
- LSN(next_pagep) = new_lsn; /* Structure assignment. */
- __ham_copy_item(dbp, hcp->page, H_KEYINDEX(hcp->indx), next_pagep);
- __ham_copy_item(dbp, hcp->page, H_DATAINDEX(hcp->indx), next_pagep);
- /*
- * We've just manually inserted a key and set of data onto
- * next_pagep; however, it's possible that our caller will
- * return without further modifying the new page, for instance
- * if DB_NODUPDATA is set and our new item is a duplicate duplicate.
- * Thus, to be on the safe side, we need to mark the page dirty
- * here. [#2996]
- *
- * Note that __ham_del_pair should dirty the page we're moving
- * the items from, so we need only dirty the new page ourselves.
- */
- if ((ret = mpf->set(mpf, next_pagep, DB_MPOOL_DIRTY)) != 0)
- goto out;
- /* Update all cursors that used to point to this item. */
- if ((ret = __ham_c_chgpg(dbc, PGNO(hcp->page), H_KEYINDEX(hcp->indx),
- PGNO(next_pagep), NUM_ENT(next_pagep) - 2)) != 0)
- goto out;
- /* Now delete the pair from the current page. */
- ret = __ham_del_pair(dbc, 0);
- /*
- * __ham_del_pair decremented nelem. This is incorrect; we
- * manually copied the element elsewhere, so the total number
- * of elements hasn't changed. Increment it again.
- *
- * !!!
- * Note that we still have the metadata page pinned, and
- * __ham_del_pair dirtied it, so we don't need to set the dirty
- * flag again.
- */
- if (!STD_LOCKING(dbc))
- hcp->hdr->nelem++;
- out:
- (void)mpf->put(mpf, hcp->page, DB_MPOOL_DIRTY);
- hcp->page = next_pagep;
- hcp->pgno = PGNO(hcp->page);
- hcp->indx = NUM_ENT(hcp->page) - 2;
- F_SET(hcp, H_EXPAND);
- F_CLR(hcp, H_DELETED);
- return (ret);
- }
- /*
- * __ham_move_offpage --
- * Replace an onpage set of duplicates with the OFFDUP structure
- * that references the duplicate page.
- *
- * XXX
- * This is really just a special case of __onpage_replace; we should
- * probably combine them.
- *
- */
- static int
- __ham_move_offpage(dbc, pagep, ndx, pgno)
- DBC *dbc;
- PAGE *pagep;
- u_int32_t ndx;
- db_pgno_t pgno;
- {
- DB *dbp;
- DBT new_dbt;
- DBT old_dbt;
- HOFFDUP od;
- db_indx_t i, *inp;
- int32_t shrink;
- u_int8_t *src;
- int ret;
- dbp = dbc->dbp;
- od.type = H_OFFDUP;
- UMRW_SET(od.unused[0]);
- UMRW_SET(od.unused[1]);
- UMRW_SET(od.unused[2]);
- od.pgno = pgno;
- ret = 0;
- if (DBC_LOGGING(dbc)) {
- new_dbt.data = &od;
- new_dbt.size = HOFFDUP_SIZE;
- old_dbt.data = P_ENTRY(dbp, pagep, ndx);
- old_dbt.size = LEN_HITEM(dbp, pagep, dbp->pgsize, ndx);
- if ((ret = __ham_replace_log(dbp, dbc->txn, &LSN(pagep), 0,
- PGNO(pagep), (u_int32_t)ndx, &LSN(pagep), -1,
- &old_dbt, &new_dbt, 0)) != 0)
- return (ret);
- } else
- LSN_NOT_LOGGED(LSN(pagep));
- shrink = LEN_HITEM(dbp, pagep, dbp->pgsize, ndx) - HOFFDUP_SIZE;
- inp = P_INP(dbp, pagep);
- if (shrink != 0) {
- /* Copy data. */
- src = (u_int8_t *)(pagep) + HOFFSET(pagep);
- memmove(src + shrink, src, inp[ndx] - HOFFSET(pagep));
- HOFFSET(pagep) += shrink;
- /* Update index table. */
- for (i = ndx; i < NUM_ENT(pagep); i++)
- inp[i] += shrink;
- }
- /* Now copy the offdup entry onto the page. */
- memcpy(P_ENTRY(dbp, pagep, ndx), &od, HOFFDUP_SIZE);
- return (ret);
- }
- /*
- * __ham_dsearch:
- * Locate a particular duplicate in a duplicate set. Make sure that
- * we exit with the cursor set appropriately.
- *
- * PUBLIC: void __ham_dsearch
- * PUBLIC: __P((DBC *, DBT *, u_int32_t *, int *, u_int32_t));
- */
- void
- __ham_dsearch(dbc, dbt, offp, cmpp, flags)
- DBC *dbc;
- DBT *dbt;
- u_int32_t *offp, flags;
- int *cmpp;
- {
- DB *dbp;
- HASH_CURSOR *hcp;
- DBT cur;
- db_indx_t i, len;
- int (*func) __P((DB *, const DBT *, const DBT *));
- u_int8_t *data;
- dbp = dbc->dbp;
- hcp = (HASH_CURSOR *)dbc->internal;
- func = dbp->dup_compare == NULL ? __bam_defcmp : dbp->dup_compare;
- i = F_ISSET(hcp, H_CONTINUE) ? hcp->dup_off: 0;
- data = HKEYDATA_DATA(H_PAIRDATA(dbp, hcp->page, hcp->indx)) + i;
- hcp->dup_tlen = LEN_HDATA(dbp, hcp->page, dbp->pgsize, hcp->indx);
- while (i < hcp->dup_tlen) {
- memcpy(&len, data, sizeof(db_indx_t));
- data += sizeof(db_indx_t);
- cur.data = data;
- cur.size = (u_int32_t)len;
- /*
- * If we find an exact match, we're done. If in a sorted
- * duplicate set and the item is larger than our test item,
- * we're done. In the latter case, if permitting partial
- * matches, it's not a failure.
- */
- *cmpp = func(dbp, dbt, &cur);
- if (*cmpp == 0)
- break;
- if (*cmpp < 0 && dbp->dup_compare != NULL) {
- if (flags == DB_GET_BOTH_RANGE)
- *cmpp = 0;
- break;
- }
- i += len + 2 * sizeof(db_indx_t);
- data += len + sizeof(db_indx_t);
- }
- *offp = i;
- hcp->dup_off = i;
- hcp->dup_len = len;
- F_SET(hcp, H_ISDUP);
- }
- #ifdef DEBUG
- /*
- * __ham_cprint --
- * Display the current cursor list.
- *
- * PUBLIC: void __ham_cprint __P((DBC *));
- */
- void
- __ham_cprint(dbc)
- DBC *dbc;
- {
- HASH_CURSOR *cp;
- cp = (HASH_CURSOR *)dbc->internal;
- fprintf(stderr, "%#0lx->%#0lx: page: %lu index: %lu",
- P_TO_ULONG(dbc), P_TO_ULONG(cp), (u_long)cp->pgno,
- (u_long)cp->indx);
- if (F_ISSET(cp, H_DELETED))
- fprintf(stderr, " (deleted)");
- fprintf(stderr, "n");
- }
- #endif /* DEBUG */
- /*
- * __ham_dcursor --
- *
- * Create an off page duplicate cursor for this cursor.
- */
- static int
- __ham_dcursor(dbc, pgno, indx)
- DBC *dbc;
- db_pgno_t pgno;
- u_int32_t indx;
- {
- DB *dbp;
- HASH_CURSOR *hcp;
- BTREE_CURSOR *dcp;
- int ret;
- dbp = dbc->dbp;
- hcp = (HASH_CURSOR *)dbc->internal;
- if ((ret = __db_c_newopd(dbc, pgno, hcp->opd, &hcp->opd)) != 0)
- return (ret);
- dcp = (BTREE_CURSOR *)hcp->opd->internal;
- dcp->pgno = pgno;
- dcp->indx = indx;
- if (dbp->dup_compare == NULL) {
- /*
- * Converting to off-page Recno trees is tricky. The
- * record number for the cursor is the index + 1 (to
- * convert to 1-based record numbers).
- */
- dcp->recno = indx + 1;
- }
- /*
- * Transfer the deleted flag from the top-level cursor to the
- * created one.
- */
- if (F_ISSET(hcp, H_DELETED)) {
- F_SET(dcp, C_DELETED);
- F_CLR(hcp, H_DELETED);
- }
- return (0);
- }
- /*
- * __ham_c_chgpg --
- * Adjust the cursors after moving an item to a new page. We only
- * move cursors that are pointing at this one item and are not
- * deleted; since we only touch non-deleted cursors, and since
- * (by definition) no item existed at the pgno/indx we're moving the
- * item to, we're guaranteed that all the cursors we affect here or
- * on abort really do refer to this one item.
- */
- static int
- __ham_c_chgpg(dbc, old_pgno, old_index, new_pgno, new_index)
- DBC *dbc;
- db_pgno_t old_pgno, new_pgno;
- u_int32_t old_index, new_index;
- {
- DB *dbp, *ldbp;
- DB_ENV *dbenv;
- DB_LSN lsn;
- DB_TXN *my_txn;
- DBC *cp;
- HASH_CURSOR *hcp;
- int found, ret;
- dbp = dbc->dbp;
- dbenv = dbp->dbenv;
- my_txn = IS_SUBTRANSACTION(dbc->txn) ? dbc->txn : NULL;
- found = 0;
- MUTEX_THREAD_LOCK(dbenv, dbenv->dblist_mutexp);
- for (ldbp = __dblist_get(dbenv, dbp->adj_fileid);
- ldbp != NULL && ldbp->adj_fileid == dbp->adj_fileid;
- ldbp = LIST_NEXT(ldbp, dblistlinks)) {
- MUTEX_THREAD_LOCK(dbenv, dbp->mutexp);
- for (cp = TAILQ_FIRST(&ldbp->active_queue); cp != NULL;
- cp = TAILQ_NEXT(cp, links)) {
- if (cp == dbc || cp->dbtype != DB_HASH)
- continue;
- hcp = (HASH_CURSOR *)cp->internal;
- /*
- * If a cursor is deleted, it doesn't refer to this
- * item--it just happens to have the same indx, but
- * it points to a former neighbor. Don't move it.
- */
- if (F_ISSET(hcp, H_DELETED))
- continue;
- if (hcp->pgno == old_pgno) {
- if (hcp->indx == old_index) {
- hcp->pgno = new_pgno;
- hcp->indx = new_index;
- } else
- continue;
- if (my_txn != NULL && cp->txn != my_txn)
- found = 1;
- }
- }
- MUTEX_THREAD_UNLOCK(dbenv, dbp->mutexp);
- }
- MUTEX_THREAD_UNLOCK(dbenv, dbenv->dblist_mutexp);
- if (found != 0 && DBC_LOGGING(dbc)) {
- if ((ret = __ham_chgpg_log(dbp, my_txn, &lsn, 0, DB_HAM_CHGPG,
- old_pgno, new_pgno, old_index, new_index)) != 0)
- return (ret);
- }
- return (0);
- }