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-rw-r--r--db2/db/db_dup.c947
1 files changed, 0 insertions, 947 deletions
diff --git a/db2/db/db_dup.c b/db2/db/db_dup.c
deleted file mode 100644
index 2673bbcd61..0000000000
--- a/db2/db/db_dup.c
+++ /dev/null
@@ -1,947 +0,0 @@
-/*-
- * See the file LICENSE for redistribution information.
- *
- * Copyright (c) 1996, 1997, 1998
- * Sleepycat Software. All rights reserved.
- */
-
-#include "config.h"
-
-#ifndef lint
-static const char sccsid[] = "@(#)db_dup.c 10.35 (Sleepycat) 12/2/98";
-#endif /* not lint */
-
-#ifndef NO_SYSTEM_INCLUDES
-#include <sys/types.h>
-
-#include <errno.h>
-#include <string.h>
-#endif
-
-#include "db_int.h"
-#include "db_page.h"
-#include "btree.h"
-#include "db_am.h"
-
-static int __db_addpage __P((DBC *,
- PAGE **, db_indx_t *, int (*)(DBC *, u_int32_t, PAGE **)));
-static int __db_dsplit __P((DBC *,
- PAGE **, db_indx_t *, u_int32_t, int (*)(DBC *, u_int32_t, PAGE **)));
-
-/*
- * __db_dput --
- * Put a duplicate item onto a duplicate page at the given index.
- *
- * PUBLIC: int __db_dput __P((DBC *, DBT *,
- * PUBLIC: PAGE **, db_indx_t *, int (*)(DBC *, u_int32_t, PAGE **)));
- */
-int
-__db_dput(dbc, dbt, pp, indxp, newfunc)
- DBC *dbc;
- DBT *dbt;
- PAGE **pp;
- db_indx_t *indxp;
- int (*newfunc) __P((DBC *, u_int32_t, PAGE **));
-{
- BOVERFLOW bo;
- DBT *data_dbtp, hdr_dbt, *hdr_dbtp;
- PAGE *pagep;
- db_indx_t size, isize;
- db_pgno_t pgno;
- int ret;
-
- /*
- * We need some access method independent threshold for when we put
- * a duplicate item onto an overflow page.
- */
- if (dbt->size > 0.25 * dbc->dbp->pgsize) {
- if ((ret = __db_poff(dbc, dbt, &pgno, newfunc)) != 0)
- return (ret);
- UMRW(bo.unused1);
- B_TSET(bo.type, B_OVERFLOW, 0);
- UMRW(bo.unused2);
- bo.tlen = dbt->size;
- bo.pgno = pgno;
- hdr_dbt.data = &bo;
- hdr_dbt.size = isize = BOVERFLOW_SIZE;
- hdr_dbtp = &hdr_dbt;
- size = BOVERFLOW_PSIZE;
- data_dbtp = NULL;
- } else {
- size = BKEYDATA_PSIZE(dbt->size);
- isize = BKEYDATA_SIZE(dbt->size);
- hdr_dbtp = NULL;
- data_dbtp = dbt;
- }
-
- pagep = *pp;
- if (size > P_FREESPACE(pagep)) {
- if (*indxp == NUM_ENT(*pp) && NEXT_PGNO(*pp) == PGNO_INVALID)
- ret = __db_addpage(dbc, pp, indxp, newfunc);
- else
- ret = __db_dsplit(dbc, pp, indxp, isize, newfunc);
- if (ret != 0)
- /*
- * XXX
- * Pages not returned to free list.
- */
- return (ret);
- pagep = *pp;
- }
-
- /*
- * Now, pagep references the page on which to insert and indx is the
- * the location to insert.
- */
- if ((ret = __db_pitem(dbc,
- pagep, (u_int32_t)*indxp, isize, hdr_dbtp, data_dbtp)) != 0)
- return (ret);
-
- (void)memp_fset(dbc->dbp->mpf, pagep, DB_MPOOL_DIRTY);
- return (0);
-}
-
-/*
- * __db_drem --
- * Remove a duplicate at the given index on the given page.
- *
- * PUBLIC: int __db_drem __P((DBC *,
- * PUBLIC: PAGE **, u_int32_t, int (*)(DBC *, PAGE *)));
- */
-int
-__db_drem(dbc, pp, indx, freefunc)
- DBC *dbc;
- PAGE **pp;
- u_int32_t indx;
- int (*freefunc) __P((DBC *, PAGE *));
-{
- PAGE *pagep;
- int ret;
-
- pagep = *pp;
-
- /* Check if we are freeing a big item. */
- if (B_TYPE(GET_BKEYDATA(pagep, indx)->type) == B_OVERFLOW) {
- if ((ret = __db_doff(dbc,
- GET_BOVERFLOW(pagep, indx)->pgno, freefunc)) != 0)
- return (ret);
- ret = __db_ditem(dbc, pagep, indx, BOVERFLOW_SIZE);
- } else
- ret = __db_ditem(dbc, pagep, indx,
- BKEYDATA_SIZE(GET_BKEYDATA(pagep, indx)->len));
- if (ret != 0)
- return (ret);
-
- if (NUM_ENT(pagep) == 0) {
- /*
- * If the page is emptied, then the page is freed and the pp
- * parameter is set to reference the next, locked page in the
- * duplicate chain, if one exists. If there was no such page,
- * then it is set to NULL.
- *
- * !!!
- * __db_relink will set the dirty bit for us.
- */
- if ((ret = __db_relink(dbc, DB_REM_PAGE, pagep, pp, 0)) != 0)
- return (ret);
- if ((ret = freefunc(dbc, pagep)) != 0)
- return (ret);
- } else
- (void)memp_fset(dbc->dbp->mpf, pagep, DB_MPOOL_DIRTY);
-
- return (0);
-}
-
-/*
- * __db_dend --
- * Find the last page in a set of offpage duplicates.
- *
- * PUBLIC: int __db_dend __P((DBC *, db_pgno_t, PAGE **));
- */
-int
-__db_dend(dbc, pgno, pp)
- DBC *dbc;
- db_pgno_t pgno;
- PAGE **pp;
-{
- DB *dbp;
- PAGE *h;
- int ret;
-
- dbp = dbc->dbp;
-
- /*
- * This implements DB_KEYLAST. The last page is returned in pp; pgno
- * should be the page number of the first page of the duplicate chain.
- *
- * *pp may be non-NULL -- if given a valid page use it.
- */
- if (*pp != NULL)
- goto started;
- for (;;) {
- if ((ret = memp_fget(dbp->mpf, &pgno, 0, pp)) != 0) {
- (void)__db_pgerr(dbp, pgno);
- return (ret);
- }
-started: h = *pp;
-
- if ((pgno = NEXT_PGNO(h)) == PGNO_INVALID)
- break;
-
- if ((ret = memp_fput(dbp->mpf, h, 0)) != 0)
- return (ret);
- }
- return (0);
-}
-
-/*
- * __db_dsplit --
- * Split a page of duplicates, calculating the split point based
- * on an element of size "size" being added at "*indxp".
- * On entry hp contains a pointer to the page-pointer of the original
- * page. On exit, it returns a pointer to the page containing "*indxp"
- * and "indxp" has been modified to reflect the index on the new page
- * where the element should be added. The function returns with
- * the page on which the insert should happen, not yet put.
- */
-static int
-__db_dsplit(dbc, hp, indxp, size, newfunc)
- DBC *dbc;
- PAGE **hp;
- db_indx_t *indxp;
- u_int32_t size;
- int (*newfunc) __P((DBC *, u_int32_t, PAGE **));
-{
- PAGE *h, *np, *tp;
- BKEYDATA *bk;
- DBT page_dbt;
- DB *dbp;
- size_t pgsize;
- db_indx_t halfbytes, i, indx, lastsum, nindex, oindex, s, sum;
- int did_indx, ret, t_ret;
-
- h = *hp;
- indx = *indxp;
- ret = 0;
- dbp = dbc->dbp;
- pgsize = dbp->pgsize;
-
- /* Create a temporary page to do compaction onto. */
- if ((ret = __os_malloc(pgsize, NULL, &tp)) != 0)
- return (ret);
-
- /* Create new page for the split. */
- if ((ret = newfunc(dbc, P_DUPLICATE, &np)) != 0) {
- __os_free(tp, pgsize);
- return (ret);
- }
-
- P_INIT(np, pgsize, PGNO(np), PGNO(h), NEXT_PGNO(h), 0,
- P_DUPLICATE);
- P_INIT(tp, pgsize, PGNO(h), PREV_PGNO(h), PGNO(np), 0,
- P_DUPLICATE);
-
- /* Figure out the split point */
- halfbytes = (pgsize - HOFFSET(h)) / 2;
- did_indx = 0;
- for (sum = 0, lastsum = 0, i = 0; i < NUM_ENT(h); i++) {
- if (i == indx) {
- sum += size;
- did_indx = 1;
- if (lastsum < halfbytes && sum >= halfbytes) {
- /* We've crossed the halfway point. */
- if ((db_indx_t)(halfbytes - lastsum) <
- (db_indx_t)(sum - halfbytes)) {
- *hp = np;
- *indxp = 0;
- } else
- *indxp = i;
- break;
- }
- *indxp = i;
- lastsum = sum;
- }
- if (B_TYPE(GET_BKEYDATA(h, i)->type) == B_KEYDATA)
- sum += BKEYDATA_SIZE(GET_BKEYDATA(h, i)->len);
- else
- sum += BOVERFLOW_SIZE;
-
- if (lastsum < halfbytes && sum >= halfbytes) {
- /* We've crossed the halfway point. */
- if ((db_indx_t)(sum - halfbytes) <
- (db_indx_t)(halfbytes - lastsum))
- i++;
- break;
- }
- }
- /*
- * Check if we have set the return values of the index pointer and
- * page pointer.
- */
- if (!did_indx) {
- *hp = np;
- *indxp = indx - i;
- }
-
- if (DB_LOGGING(dbc)) {
- page_dbt.size = dbp->pgsize;
- page_dbt.data = h;
- if ((ret = __db_split_log(dbp->dbenv->lg_info,
- dbc->txn, &LSN(h), 0, DB_SPLITOLD, dbp->log_fileid,
- PGNO(h), &page_dbt, &LSN(h))) != 0) {
- __os_free(tp, pgsize);
- return (ret);
- }
- LSN(tp) = LSN(h);
- }
-
- /*
- * If it's a btree, adjust the cursors.
- *
- * i is the index of the first element to move onto the new page.
- */
- if (dbp->type == DB_BTREE)
- __bam_ca_split(dbp, PGNO(h), PGNO(h), PGNO(np), i, 0);
-
- for (nindex = 0, oindex = i; oindex < NUM_ENT(h); oindex++) {
- bk = GET_BKEYDATA(h, oindex);
- if (B_TYPE(bk->type) == B_KEYDATA)
- s = BKEYDATA_SIZE(bk->len);
- else
- s = BOVERFLOW_SIZE;
-
- np->inp[nindex++] = HOFFSET(np) -= s;
- memcpy((u_int8_t *)np + HOFFSET(np), bk, s);
- NUM_ENT(np)++;
- }
-
- /*
- * Now do data compaction by copying the remaining stuff onto the
- * temporary page and then copying it back to the real page.
- */
- for (nindex = 0, oindex = 0; oindex < i; oindex++) {
- bk = GET_BKEYDATA(h, oindex);
- if (B_TYPE(bk->type) == B_KEYDATA)
- s = BKEYDATA_SIZE(bk->len);
- else
- s = BOVERFLOW_SIZE;
-
- tp->inp[nindex++] = HOFFSET(tp) -= s;
- memcpy((u_int8_t *)tp + HOFFSET(tp), bk, s);
- NUM_ENT(tp)++;
- }
-
- /*
- * This page (the temporary) should be only half full, so we do two
- * memcpy's, one for the top of the page and one for the bottom of
- * the page. This way we avoid copying the middle which should be
- * about half a page.
- */
- memcpy(h, tp, LOFFSET(tp));
- memcpy((u_int8_t *)h + HOFFSET(tp),
- (u_int8_t *)tp + HOFFSET(tp), pgsize - HOFFSET(tp));
- __os_free(tp, pgsize);
-
- if (DB_LOGGING(dbc)) {
- /*
- * XXX
- * If either of these fails, are we leaving pages pinned?
- * Yes, but it seems like this happens in error case.
- */
- page_dbt.size = pgsize;
- page_dbt.data = h;
- if ((ret = __db_split_log(dbp->dbenv->lg_info,
- dbc->txn, &LSN(h), 0, DB_SPLITNEW, dbp->log_fileid,
- PGNO(h), &page_dbt, &LSN(h))) != 0)
- return (ret);
-
- page_dbt.size = pgsize;
- page_dbt.data = np;
- if ((ret = __db_split_log(dbp->dbenv->lg_info,
- dbc->txn, &LSN(np), 0, DB_SPLITNEW, dbp->log_fileid,
- PGNO(np), &page_dbt, &LSN(np))) != 0)
- return (ret);
- }
-
- /*
- * Finally, if there was a next page after the page being
- * split, fix its prev pointer.
- */
- if (np->next_pgno != PGNO_INVALID)
- ret = __db_relink(dbc, DB_ADD_PAGE, np, NULL, 1);
-
- /*
- * Figure out if the location we're interested in is on the new
- * page, and if so, reset the callers' pointer. Push the other
- * page back to the store.
- */
- if (*hp == h)
- t_ret = memp_fput(dbp->mpf, np, DB_MPOOL_DIRTY);
- else
- t_ret = memp_fput(dbp->mpf, h, DB_MPOOL_DIRTY);
-
- return (ret != 0 ? ret : t_ret);
-}
-
-/*
- * __db_ditem --
- * Remove an item from a page.
- *
- * PUBLIC: int __db_ditem __P((DBC *, PAGE *, u_int32_t, u_int32_t));
- */
-int
-__db_ditem(dbc, pagep, indx, nbytes)
- DBC *dbc;
- PAGE *pagep;
- u_int32_t indx, nbytes;
-{
- DB *dbp;
- DBT ldbt;
- db_indx_t cnt, offset;
- int ret;
- u_int8_t *from;
-
- dbp = dbc->dbp;
- if (DB_LOGGING(dbc)) {
- ldbt.data = P_ENTRY(pagep, indx);
- ldbt.size = nbytes;
- if ((ret = __db_addrem_log(dbp->dbenv->lg_info, dbc->txn,
- &LSN(pagep), 0, DB_REM_DUP, dbp->log_fileid, PGNO(pagep),
- (u_int32_t)indx, nbytes, &ldbt, NULL, &LSN(pagep))) != 0)
- return (ret);
- }
-
- /*
- * If there's only a single item on the page, we don't have to
- * work hard.
- */
- if (NUM_ENT(pagep) == 1) {
- NUM_ENT(pagep) = 0;
- HOFFSET(pagep) = dbp->pgsize;
- return (0);
- }
-
- /*
- * Pack the remaining key/data items at the end of the page. Use
- * memmove(3), the regions may overlap.
- */
- from = (u_int8_t *)pagep + HOFFSET(pagep);
- memmove(from + nbytes, from, pagep->inp[indx] - HOFFSET(pagep));
- HOFFSET(pagep) += nbytes;
-
- /* Adjust the indices' offsets. */
- offset = pagep->inp[indx];
- for (cnt = 0; cnt < NUM_ENT(pagep); ++cnt)
- if (pagep->inp[cnt] < offset)
- pagep->inp[cnt] += nbytes;
-
- /* Shift the indices down. */
- --NUM_ENT(pagep);
- if (indx != NUM_ENT(pagep))
- memmove(&pagep->inp[indx], &pagep->inp[indx + 1],
- sizeof(db_indx_t) * (NUM_ENT(pagep) - indx));
-
- /* If it's a btree, adjust the cursors. */
- if (dbp->type == DB_BTREE)
- __bam_ca_di(dbp, PGNO(pagep), indx, -1);
-
- return (0);
-}
-
-/*
- * __db_pitem --
- * Put an item on a page.
- *
- * PUBLIC: int __db_pitem
- * PUBLIC: __P((DBC *, PAGE *, u_int32_t, u_int32_t, DBT *, DBT *));
- */
-int
-__db_pitem(dbc, pagep, indx, nbytes, hdr, data)
- DBC *dbc;
- PAGE *pagep;
- u_int32_t indx;
- u_int32_t nbytes;
- DBT *hdr, *data;
-{
- DB *dbp;
- BKEYDATA bk;
- DBT thdr;
- int ret;
- u_int8_t *p;
-
- /*
- * Put a single item onto a page. The logic figuring out where to
- * insert and whether it fits is handled in the caller. All we do
- * here is manage the page shuffling. We cheat a little bit in that
- * we don't want to copy the dbt on a normal put twice. If hdr is
- * NULL, we create a BKEYDATA structure on the page, otherwise, just
- * copy the caller's information onto the page.
- *
- * This routine is also used to put entries onto the page where the
- * entry is pre-built, e.g., during recovery. In this case, the hdr
- * will point to the entry, and the data argument will be NULL.
- *
- * !!!
- * There's a tremendous potential for off-by-one errors here, since
- * the passed in header sizes must be adjusted for the structure's
- * placeholder for the trailing variable-length data field.
- */
- dbp = dbc->dbp;
- if (DB_LOGGING(dbc))
- if ((ret = __db_addrem_log(dbp->dbenv->lg_info, dbc->txn,
- &LSN(pagep), 0, DB_ADD_DUP, dbp->log_fileid, PGNO(pagep),
- (u_int32_t)indx, nbytes, hdr, data, &LSN(pagep))) != 0)
- return (ret);
-
- if (hdr == NULL) {
- B_TSET(bk.type, B_KEYDATA, 0);
- bk.len = data == NULL ? 0 : data->size;
-
- thdr.data = &bk;
- thdr.size = SSZA(BKEYDATA, data);
- hdr = &thdr;
- }
-
- /* Adjust the index table, then put the item on the page. */
- if (indx != NUM_ENT(pagep))
- memmove(&pagep->inp[indx + 1], &pagep->inp[indx],
- sizeof(db_indx_t) * (NUM_ENT(pagep) - indx));
- HOFFSET(pagep) -= nbytes;
- pagep->inp[indx] = HOFFSET(pagep);
- ++NUM_ENT(pagep);
-
- p = P_ENTRY(pagep, indx);
- memcpy(p, hdr->data, hdr->size);
- if (data != NULL)
- memcpy(p + hdr->size, data->data, data->size);
-
- /* If it's a btree, adjust the cursors. */
- if (dbp->type == DB_BTREE)
- __bam_ca_di(dbp, PGNO(pagep), indx, 1);
-
- return (0);
-}
-
-/*
- * __db_relink --
- * Relink around a deleted page.
- *
- * PUBLIC: int __db_relink __P((DBC *, u_int32_t, PAGE *, PAGE **, int));
- */
-int
-__db_relink(dbc, add_rem, pagep, new_next, needlock)
- DBC *dbc;
- u_int32_t add_rem;
- PAGE *pagep, **new_next;
- int needlock;
-{
- DB *dbp;
- PAGE *np, *pp;
- DB_LOCK npl, ppl;
- DB_LSN *nlsnp, *plsnp;
- int ret;
-
- ret = 0;
- np = pp = NULL;
- npl = ppl = LOCK_INVALID;
- nlsnp = plsnp = NULL;
- dbp = dbc->dbp;
-
- /*
- * Retrieve and lock the one/two pages. For a remove, we may need
- * two pages (the before and after). For an add, we only need one
- * because, the split took care of the prev.
- */
- if (pagep->next_pgno != PGNO_INVALID) {
- if (needlock && (ret = __bam_lget(dbc,
- 0, pagep->next_pgno, DB_LOCK_WRITE, &npl)) != 0)
- goto err;
- if ((ret = memp_fget(dbp->mpf,
- &pagep->next_pgno, 0, &np)) != 0) {
- (void)__db_pgerr(dbp, pagep->next_pgno);
- goto err;
- }
- nlsnp = &np->lsn;
- }
- if (add_rem == DB_REM_PAGE && pagep->prev_pgno != PGNO_INVALID) {
- if (needlock && (ret = __bam_lget(dbc,
- 0, pagep->prev_pgno, DB_LOCK_WRITE, &ppl)) != 0)
- goto err;
- if ((ret = memp_fget(dbp->mpf,
- &pagep->prev_pgno, 0, &pp)) != 0) {
- (void)__db_pgerr(dbp, pagep->next_pgno);
- goto err;
- }
- plsnp = &pp->lsn;
- }
-
- /* Log the change. */
- if (DB_LOGGING(dbc)) {
- if ((ret = __db_relink_log(dbp->dbenv->lg_info, dbc->txn,
- &pagep->lsn, 0, add_rem, dbp->log_fileid,
- pagep->pgno, &pagep->lsn,
- pagep->prev_pgno, plsnp, pagep->next_pgno, nlsnp)) != 0)
- goto err;
- if (np != NULL)
- np->lsn = pagep->lsn;
- if (pp != NULL)
- pp->lsn = pagep->lsn;
- }
-
- /*
- * Modify and release the two pages.
- *
- * !!!
- * The parameter new_next gets set to the page following the page we
- * are removing. If there is no following page, then new_next gets
- * set to NULL.
- */
- if (np != NULL) {
- if (add_rem == DB_ADD_PAGE)
- np->prev_pgno = pagep->pgno;
- else
- np->prev_pgno = pagep->prev_pgno;
- if (new_next == NULL)
- ret = memp_fput(dbp->mpf, np, DB_MPOOL_DIRTY);
- else {
- *new_next = np;
- ret = memp_fset(dbp->mpf, np, DB_MPOOL_DIRTY);
- }
- if (ret != 0)
- goto err;
- if (needlock)
- (void)__bam_lput(dbc, npl);
- } else if (new_next != NULL)
- *new_next = NULL;
-
- if (pp != NULL) {
- pp->next_pgno = pagep->next_pgno;
- if ((ret = memp_fput(dbp->mpf, pp, DB_MPOOL_DIRTY)) != 0)
- goto err;
- if (needlock)
- (void)__bam_lput(dbc, ppl);
- }
- return (0);
-
-err: if (np != NULL)
- (void)memp_fput(dbp->mpf, np, 0);
- if (needlock && npl != LOCK_INVALID)
- (void)__bam_lput(dbc, npl);
- if (pp != NULL)
- (void)memp_fput(dbp->mpf, pp, 0);
- if (needlock && ppl != LOCK_INVALID)
- (void)__bam_lput(dbc, ppl);
- return (ret);
-}
-
-/*
- * __db_ddup --
- * Delete an offpage chain of duplicates.
- *
- * PUBLIC: int __db_ddup __P((DBC *, db_pgno_t, int (*)(DBC *, PAGE *)));
- */
-int
-__db_ddup(dbc, pgno, freefunc)
- DBC *dbc;
- db_pgno_t pgno;
- int (*freefunc) __P((DBC *, PAGE *));
-{
- DB *dbp;
- PAGE *pagep;
- DBT tmp_dbt;
- int ret;
-
- dbp = dbc->dbp;
- do {
- if ((ret = memp_fget(dbp->mpf, &pgno, 0, &pagep)) != 0) {
- (void)__db_pgerr(dbp, pgno);
- return (ret);
- }
-
- if (DB_LOGGING(dbc)) {
- tmp_dbt.data = pagep;
- tmp_dbt.size = dbp->pgsize;
- if ((ret = __db_split_log(dbp->dbenv->lg_info,
- dbc->txn, &LSN(pagep), 0, DB_SPLITOLD,
- dbp->log_fileid, PGNO(pagep), &tmp_dbt,
- &LSN(pagep))) != 0)
- return (ret);
- }
- pgno = pagep->next_pgno;
- if ((ret = freefunc(dbc, pagep)) != 0)
- return (ret);
- } while (pgno != PGNO_INVALID);
-
- return (0);
-}
-
-/*
- * __db_addpage --
- * Create a new page and link it onto the next_pgno field of the
- * current page.
- */
-static int
-__db_addpage(dbc, hp, indxp, newfunc)
- DBC *dbc;
- PAGE **hp;
- db_indx_t *indxp;
- int (*newfunc) __P((DBC *, u_int32_t, PAGE **));
-{
- DB *dbp;
- PAGE *newpage;
- int ret;
-
- dbp = dbc->dbp;
- if ((ret = newfunc(dbc, P_DUPLICATE, &newpage)) != 0)
- return (ret);
-
- if (DB_LOGGING(dbc)) {
- if ((ret = __db_addpage_log(dbp->dbenv->lg_info,
- dbc->txn, &LSN(*hp), 0, dbp->log_fileid,
- PGNO(*hp), &LSN(*hp), PGNO(newpage), &LSN(newpage))) != 0) {
- return (ret);
- }
- LSN(newpage) = LSN(*hp);
- }
-
- PREV_PGNO(newpage) = PGNO(*hp);
- NEXT_PGNO(*hp) = PGNO(newpage);
-
- if ((ret = memp_fput(dbp->mpf, *hp, DB_MPOOL_DIRTY)) != 0)
- return (ret);
- *hp = newpage;
- *indxp = 0;
- return (0);
-}
-
-/*
- * __db_dsearch --
- * Search a set of duplicates for the proper position for a new duplicate.
- *
- * + pgno is the page number of the page on which to begin searching.
- * Since we can continue duplicate searches, it might not be the first
- * page.
- *
- * + If we are continuing a search, then *pp may be non-NULL in which
- * case we do not have to retrieve the page.
- *
- * + If we are continuing a search, then *indxp contains the first
- * on pgno of where we should begin the search.
- *
- * NOTE: if there is no comparison function, then continuing is
- * meaningless, and *pp should always be NULL and *indxp will be
- * ignored.
- *
- * 3 return values::
- *
- * + pp is the returned page pointer of where this element should go.
- * + indxp is the returned index on that page
- * + cmpp is the returned final comparison result.
- *
- * PUBLIC: int __db_dsearch __P((DBC *,
- * PUBLIC: int, DBT *, db_pgno_t, db_indx_t *, PAGE **, int *));
- */
-int
-__db_dsearch(dbc, is_insert, dbt, pgno, indxp, pp, cmpp)
- DBC *dbc;
- int is_insert, *cmpp;
- DBT *dbt;
- db_pgno_t pgno;
- db_indx_t *indxp;
- PAGE **pp;
-{
- DB *dbp;
- PAGE *h;
- db_indx_t base, indx, lim, save_indx;
- db_pgno_t save_pgno;
- int ret;
-
- dbp = dbc->dbp;
-
- if (dbp->dup_compare == NULL) {
- /*
- * We may have been given a valid page, but we may not be
- * able to use it. The problem is that the application is
- * doing a join and we're trying to continue the search,
- * but since the items aren't sorted, we can't. Discard
- * the page if it's not the one we're going to start with
- * anyway.
- */
- if (*pp != NULL && (*pp)->pgno != pgno) {
- if ((ret = memp_fput(dbp->mpf, *pp, 0)) != 0)
- return (ret);
- *pp = NULL;
- }
-
- /*
- * If no duplicate function is specified, just go to the end
- * of the duplicate set.
- */
- if (is_insert) {
- if ((ret = __db_dend(dbc, pgno, pp)) != 0)
- return (ret);
- *indxp = NUM_ENT(*pp);
- return (0);
- }
-
- /*
- * We are looking for a specific duplicate, so do a linear
- * search.
- */
- if (*pp != NULL)
- goto nocmp_started;
- for (;;) {
- if ((ret = memp_fget(dbp->mpf, &pgno, 0, pp)) != 0)
- goto pg_err;
-nocmp_started: h = *pp;
-
- for (*indxp = 0; *indxp < NUM_ENT(h); ++*indxp) {
- if ((*cmpp = __bam_cmp(dbp,
- dbt, h, *indxp, __bam_defcmp)) != 0)
- continue;
- /*
- * The duplicate may have already been deleted,
- * if it's a btree page, in which case we skip
- * it.
- */
- if (dbp->type == DB_BTREE &&
- B_DISSET(GET_BKEYDATA(h, *indxp)->type))
- continue;
-
- return (0);
- }
-
- if ((pgno = h->next_pgno) == PGNO_INVALID)
- break;
-
- if ((ret = memp_fput(dbp->mpf, h, 0)) != 0)
- return (ret);
- }
- *cmpp = 1; /* We didn't succeed... */
- return (0);
- }
-
- /*
- * We have a comparison routine, i.e., the duplicates are sorted.
- * Walk through the chain of duplicates, checking the last entry
- * on each page to decide if it's the page we want to search.
- *
- * *pp may be non-NULL -- if we were given a valid page (e.g., are
- * in mid-search), then use the provided page.
- */
- if (*pp != NULL)
- goto cmp_started;
- for (;;) {
- if ((ret = memp_fget(dbp->mpf, &pgno, 0, pp)) != 0)
- goto pg_err;
-cmp_started: h = *pp;
-
- if ((pgno = h->next_pgno) == PGNO_INVALID || __bam_cmp(dbp,
- dbt, h, h->entries - 1, dbp->dup_compare) <= 0)
- break;
- /*
- * Even when continuing a search, make sure we don't skip
- * entries on a new page
- */
- *indxp = 0;
-
- if ((ret = memp_fput(dbp->mpf, h, 0)) != 0)
- return (ret);
- }
-
- /* Next, do a binary search on the page. */
- base = F_ISSET(dbc, DBC_CONTINUE) ? *indxp : 0;
- for (lim = NUM_ENT(h) - base; lim != 0; lim >>= 1) {
- indx = base + (lim >> 1);
- if ((*cmpp = __bam_cmp(dbp,
- dbt, h, indx, dbp->dup_compare)) == 0) {
- *indxp = indx;
-
- if (dbp->type != DB_BTREE ||
- !B_DISSET(GET_BKEYDATA(h, *indxp)->type))
- return (0);
- goto check_delete;
- }
- if (*cmpp > 0) {
- base = indx + 1;
- lim--;
- }
- }
-
- /*
- * Base references the smallest index larger than the supplied DBT's
- * data item, potentially both 0 and NUM_ENT.
- */
- *indxp = base;
- return (0);
-
-check_delete:
- /*
- * The duplicate may have already been deleted, if it's a btree page,
- * in which case we wander around, hoping to find an entry that hasn't
- * been deleted. First, wander in a forwardly direction.
- */
- save_pgno = (*pp)->pgno;
- save_indx = *indxp;
- for (++*indxp;;) {
- for (; *indxp < NUM_ENT(h); ++*indxp) {
- if ((*cmpp = __bam_cmp(dbp,
- dbt, h, *indxp, dbp->dup_compare)) != 0)
- goto check_delete_rev;
-
- if (!B_DISSET(GET_BKEYDATA(h, *indxp)->type))
- return (0);
- }
- if ((pgno = h->next_pgno) == PGNO_INVALID)
- break;
-
- if ((ret = memp_fput(dbp->mpf, h, 0)) != 0)
- return (ret);
-
- if ((ret = memp_fget(dbp->mpf, &pgno, 0, pp)) != 0)
- goto pg_err;
- h = *pp;
-
- *indxp = 0;
- }
-
-check_delete_rev:
- /* Go back to where we started, and wander in a backwardly direction. */
- if (h->pgno != save_pgno) {
- if ((ret = memp_fput(dbp->mpf, h, 0)) != 0)
- return (ret);
- if ((ret = memp_fget(dbp->mpf, &save_pgno, 0, pp)) != 0)
- goto pg_err;
- h = *pp;
- }
-
- for (;;) {
- while (*indxp > 0) {
- --*indxp;
- if ((*cmpp = __bam_cmp(dbp,
- dbt, h, *indxp, dbp->dup_compare)) != 0)
- goto check_delete_fail;
-
- if (!B_DISSET(GET_BKEYDATA(h, *indxp)->type))
- return (0);
- }
- if ((pgno = h->prev_pgno) == PGNO_INVALID)
- break;
-
- if ((ret = memp_fput(dbp->mpf, h, 0)) != 0)
- return (ret);
-
- if ((ret = memp_fget(dbp->mpf, &pgno, 0, pp)) != 0)
- goto pg_err;
- h = *pp;
-
- *indxp = NUM_ENT(h);
- }
-
-check_delete_fail:
- *cmpp = 1; /* We didn't succeed... */
- return (0);
-
-pg_err: __db_pgerr(dbp, pgno);
- return (ret);
-}