diff options
Diffstat (limited to 'db2/db/db_dup.c')
| -rw-r--r-- | db2/db/db_dup.c | 947 |
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 2673bbc..0000000 --- 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); -} |