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Diffstat (limited to 'bdb/hash/hash_dup.c')
-rw-r--r-- | bdb/hash/hash_dup.c | 805 |
1 files changed, 805 insertions, 0 deletions
diff --git a/bdb/hash/hash_dup.c b/bdb/hash/hash_dup.c new file mode 100644 index 00000000000..f5fbf4f472f --- /dev/null +++ b/bdb/hash/hash_dup.c @@ -0,0 +1,805 @@ +/*- + * See the file LICENSE for redistribution information. + * + * Copyright (c) 1996, 1997, 1998, 1999, 2000 + * 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 11.49 2000/12/21 21:54:35 margo Exp $"; +#endif /* not lint */ + +/* + * PACKAGE: hashing + * + * DESCRIPTION: + * Manipulation of duplicates for the hash package. + * + * ROUTINES: + * + * External + * __add_dup + * Internal + */ + +#ifndef NO_SYSTEM_INCLUDES +#include <sys/types.h> + +#include <string.h> +#endif + +#include "db_int.h" +#include "db_page.h" +#include "hash.h" +#include "btree.h" +#include "txn.h" + +static int __ham_check_move __P((DBC *, u_int32_t)); +static int __ham_dcursor __P((DBC *, db_pgno_t, u_int32_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; + HASH_CURSOR *hcp; + DBT pval, tmp_val; + u_int32_t add_bytes, new_size; + int cmp, ret; + u_int8_t *hk; + + dbp = dbc->dbp; + 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(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(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(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(hcp->page, dbp->pgsize, + hcp->indx); + if ((ret = __ham_make_dup(dbp->dbenv, + &pval, &tmp_val, &dbc->rdata.data, + &dbc->rdata.ulen)) != 0 || (ret = + __ham_replpair(dbc, &tmp_val, 1)) != 0) + return (ret); + hk = H_PAIRDATA(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->rdata.data, &dbc->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); + + /* dup dups are not supported w/ sorted dups */ + if (cmp == 0) + return (__db_duperr(dbp, flags)); + } else { + hcp->dup_tlen = LEN_HDATA(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 = memp_fset(dbp->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 += DUP_SIZE(nval->size); + break; + case DB_KEYFIRST: + case DB_KEYLAST: + case DB_BEFORE: + hcp->dup_tlen += 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(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; +{ + DB *dbp; + DBC **hcs; + DB_LSN lsn; + PAGE *dp; + HASH_CURSOR *hcp; + BOVERFLOW bo; + DBT dbt; + HOFFPAGE ho; + db_indx_t i, len, off; + int c, ret, t_ret; + u_int8_t *p, *pend; + + dbp = dbc->dbp; + 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) + return (ret); + + /* + * Now put the duplicates onto the new page. + */ + dbt.flags = 0; + switch (HPAGE_PTYPE(H_PAIRDATA(hcp->page, hcp->indx))) { + case H_KEYDATA: + /* Simple case, one key on page; move it to dup page. */ + dbt.size = LEN_HDATA(hcp->page, dbp->pgsize, hcp->indx); + dbt.data = HKEYDATA_DATA(H_PAIRDATA(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(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) { + memp_fset(dbp->mpf, dp, DB_MPOOL_DIRTY); + /* + * Update any other cursors + */ + if (hcs != NULL && DB_LOGGING(dbc) + && IS_SUBTRANSACTION(dbc->txn)) { + if ((ret = __ham_chgpg_log(dbp->dbenv, + dbc->txn, &lsn, 0, dbp->log_fileid, + 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(hcp->page, hcp->indx)); + pend = p + + LEN_HDATA(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 + */ + 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 out; + off += len + 2 * sizeof(db_indx_t); + } +out: break; + + default: + ret = __db_pgfmt(dbp, (u_long)hcp->pgno); + break; + } + if (ret == 0) { + /* + * Now attach this to the source page in place of + * the old duplicate item. + */ + __ham_move_offpage(dbc, hcp->page, + (u_int32_t)H_DATAINDEX(hcp->indx), PGNO(dp)); + + ret = memp_fset(dbp->mpf, hcp->page, DB_MPOOL_DIRTY); + if ((t_ret = memp_fput(dbp->mpf, dp, DB_MPOOL_DIRTY)) != 0) + ret = t_ret; + hcp->dup_tlen = hcp->dup_off = hcp->dup_len = 0; + } else + (void)__db_free(dbc, dp); + + if (hcs != NULL) + __os_free(hcs, 0); + + 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; + HASH_CURSOR *hcp; + DBT k, d; + DB_LSN new_lsn; + 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; + hcp = (HASH_CURSOR *)dbc->internal; + + hk = H_PAIRDATA(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(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(hcp->page))) + return (0); + + if (!ISBIG(hcp, new_datalen) && add_len <= P_FREESPACE(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(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 = memp_fput(dbp->mpf, next_pagep, 0)) != 0) + return (ret); + + if ((ret = memp_fget(dbp->mpf, + &next_pgno, DB_MPOOL_CREATE, &next_pagep)) != 0) + return (ret); + + if (P_FREESPACE(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(next_pagep) < new_datalen && (ret = + __ham_add_ovflpage(dbc, next_pagep, 1, &next_pagep)) != 0) { + (void)memp_fput(dbp->mpf, next_pagep, 0); + return (ret); + } + + /* Copy the item to the new page. */ + if (DB_LOGGING(dbc)) { + rectype = PUTPAIR; + k.flags = 0; + d.flags = 0; + if (HPAGE_PTYPE( + H_PAIRKEY(hcp->page, hcp->indx)) == H_OFFPAGE) { + rectype |= PAIR_KEYMASK; + k.data = H_PAIRKEY(hcp->page, hcp->indx); + k.size = HOFFPAGE_SIZE; + } else { + k.data = + HKEYDATA_DATA(H_PAIRKEY(hcp->page, hcp->indx)); + k.size = LEN_HKEY(hcp->page, dbp->pgsize, hcp->indx); + } + + if (HPAGE_PTYPE(hk) == H_OFFPAGE) { + rectype |= PAIR_DATAMASK; + d.data = H_PAIRDATA(hcp->page, hcp->indx); + d.size = HOFFPAGE_SIZE; + } else { + if (HPAGE_PTYPE(H_PAIRDATA(hcp->page, hcp->indx)) + == H_DUPLICATE) + rectype |= PAIR_DUPMASK; + d.data = + HKEYDATA_DATA(H_PAIRDATA(hcp->page, hcp->indx)); + d.size = LEN_HDATA(hcp->page, dbp->pgsize, hcp->indx); + } + + if ((ret = __ham_insdel_log(dbp->dbenv, + dbc->txn, &new_lsn, 0, rectype, + dbp->log_fileid, PGNO(next_pagep), + (u_int32_t)NUM_ENT(next_pagep), &LSN(next_pagep), + &k, &d)) != 0) { + (void)memp_fput(dbp->mpf, next_pagep, 0); + return (ret); + } + + /* Move lsn onto page. */ + LSN(next_pagep) = new_lsn; /* Structure assignment. */ + } + + __ham_copy_item(dbp->pgsize, + hcp->page, H_KEYINDEX(hcp->indx), next_pagep); + __ham_copy_item(dbp->pgsize, + 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 = memp_fset(dbp->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. + */ + if (!STD_LOCKING(dbc)) + hcp->hdr->nelem++; + +out: + (void)memp_fput(dbp->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. + * + * PUBLIC: void __ham_move_offpage __P((DBC *, PAGE *, u_int32_t, db_pgno_t)); + */ +void +__ham_move_offpage(dbc, pagep, ndx, pgno) + DBC *dbc; + PAGE *pagep; + u_int32_t ndx; + db_pgno_t pgno; +{ + DB *dbp; + HASH_CURSOR *hcp; + DBT new_dbt; + DBT old_dbt; + HOFFDUP od; + db_indx_t i; + int32_t shrink; + u_int8_t *src; + + dbp = dbc->dbp; + hcp = (HASH_CURSOR *)dbc->internal; + od.type = H_OFFDUP; + UMRW_SET(od.unused[0]); + UMRW_SET(od.unused[1]); + UMRW_SET(od.unused[2]); + od.pgno = pgno; + + if (DB_LOGGING(dbc)) { + new_dbt.data = &od; + new_dbt.size = HOFFDUP_SIZE; + old_dbt.data = P_ENTRY(pagep, ndx); + old_dbt.size = LEN_HITEM(pagep, dbp->pgsize, ndx); + (void)__ham_replace_log(dbp->dbenv, + dbc->txn, &LSN(pagep), 0, dbp->log_fileid, + PGNO(pagep), (u_int32_t)ndx, &LSN(pagep), -1, + &old_dbt, &new_dbt, 0); + } + + shrink = LEN_HITEM(pagep, dbp->pgsize, ndx) - HOFFDUP_SIZE; + + if (shrink != 0) { + /* Copy data. */ + src = (u_int8_t *)(pagep) + HOFFSET(pagep); + memmove(src + shrink, src, pagep->inp[ndx] - HOFFSET(pagep)); + HOFFSET(pagep) += shrink; + + /* Update index table. */ + for (i = ndx; i < NUM_ENT(pagep); i++) + pagep->inp[i] += shrink; + } + + /* Now copy the offdup entry onto the page. */ + memcpy(P_ENTRY(pagep, ndx), &od, HOFFDUP_SIZE); +} + +/* + * __ham_dsearch: + * Locate a particular duplicate in a duplicate set. Make sure that + * we exit with the cursor set appropriately. + * + * PUBLIC: void __ham_dsearch __P((DBC *, DBT *, u_int32_t *, int *)); + */ +void +__ham_dsearch(dbc, dbt, offp, cmpp) + DBC *dbc; + DBT *dbt; + u_int32_t *offp; + 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; + if (dbp->dup_compare == NULL) + func = __bam_defcmp; + else + func = dbp->dup_compare; + + i = F_ISSET(hcp, H_CONTINUE) ? hcp->dup_off: 0; + data = HKEYDATA_DATA(H_PAIRDATA(hcp->page, hcp->indx)) + i; + hcp->dup_tlen = LEN_HDATA(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; + *cmpp = func(dbp, dbt, &cur); + if (*cmpp == 0 || (*cmpp < 0 && dbp->dup_compare != NULL)) + 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: int __ham_cprint __P((DB *)); + */ +int +__ham_cprint(dbp) + DB *dbp; +{ + HASH_CURSOR *cp; + DBC *dbc; + + MUTEX_THREAD_LOCK(dbp->dbenv, dbp->mutexp); + for (dbc = TAILQ_FIRST(&dbp->active_queue); + dbc != NULL; dbc = TAILQ_NEXT(dbc, links)) { + 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"); + } + MUTEX_THREAD_UNLOCK(dbp->dbenv, dbp->mutexp); + + return (0); +} +#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; + DBC *dbc_nopd; + HASH_CURSOR *hcp; + BTREE_CURSOR *dcp; + int ret; + + dbp = dbc->dbp; + + if ((ret = __db_c_newopd(dbc, pgno, &dbc_nopd)) != 0) + return (ret); + + dcp = (BTREE_CURSOR *)dbc_nopd->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. + */ + hcp = (HASH_CURSOR *)dbc->internal; + if (F_ISSET(hcp, H_DELETED)) { + F_SET(dcp, C_DELETED); + F_CLR(hcp, H_DELETED); + } + + /* Stack the cursors and reset the initial cursor's index. */ + hcp->opd = dbc_nopd; + + return (0); +} |