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Diffstat (limited to 'db2/include/hash.h')
-rw-r--r-- | db2/include/hash.h | 211 |
1 files changed, 211 insertions, 0 deletions
diff --git a/db2/include/hash.h b/db2/include/hash.h new file mode 100644 index 0000000000..cb8ea350f5 --- /dev/null +++ b/db2/include/hash.h @@ -0,0 +1,211 @@ +/*- + * See the file LICENSE for redistribution information. + * + * Copyright (c) 1996, 1997 + * Sleepycat Software. All rights reserved. + */ +/* + * Copyright (c) 1990, 1993, 1994 + * Margo Seltzer. 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. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Berkeley and its contributors. + * 4. 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. + * + * @(#)hash.h 10.6 (Sleepycat) 8/18/97 + */ + +/* Cursor structure definitions. */ +typedef struct cursor_t { + DBC *db_cursor; + db_pgno_t bucket; /* Bucket we are traversing. */ + DB_LOCK lock; /* Lock held on the current bucket. */ + PAGE *pagep; /* The current page. */ + db_pgno_t pgno; /* Current page number. */ + db_indx_t bndx; /* Index within the current page. */ + PAGE *dpagep; /* Duplicate page pointer. */ + db_pgno_t dpgno; /* Duplicate page number. */ + db_indx_t dndx; /* Index within a duplicate set. */ + db_indx_t dup_off; /* Offset within a duplicate set. */ + db_indx_t dup_len; /* Length of current duplicate. */ + db_indx_t dup_tlen; /* Total length of duplicate entry. */ + u_int32_t seek_size; /* Number of bytes we need for add. */ + db_pgno_t seek_found_page;/* Page on which we can insert. */ + u_int32_t big_keylen; /* Length of big_key buffer. */ + void *big_key; /* Temporary buffer for big keys. */ + u_int32_t big_datalen; /* Length of big_data buffer. */ + void *big_data; /* Temporary buffer for big data. */ +#define H_OK 0x0001 +#define H_NOMORE 0x0002 +#define H_DELETED 0x0004 +#define H_ISDUP 0x0008 +#define H_EXPAND 0x0020 + u_int32_t flags; /* Is cursor inside a dup set. */ +} HASH_CURSOR; + +#define IS_VALID(C) ((C)->bucket != BUCKET_INVALID) + + +typedef struct htab { /* Memory resident data structure. */ + DB *dbp; /* Pointer to parent db structure. */ + DB_LOCK hlock; /* Metadata page lock. */ + HASHHDR *hdr; /* Pointer to meta-data page. */ + u_int32_t (*hash) __P((const void *, u_int32_t)); /* Hash Function */ + PAGE *split_buf; /* Temporary buffer for splits. */ + int local_errno; /* Error Number -- for DBM compatability */ + u_long hash_accesses; /* Number of accesses to this table. */ + u_long hash_collisions; /* Number of collisions on search. */ + u_long hash_expansions; /* Number of times we added a bucket. */ + u_long hash_overflows; /* Number of overflow pages. */ + u_long hash_bigpages; /* Number of big key/data pages. */ +} HTAB; + +/* + * Macro used for interface functions to set the txnid in the DBP. + */ +#define SET_LOCKER(D, T) ((D)->txn = (T)) + +/* + * More interface macros used to get/release the meta data page. + */ +#define GET_META(D, H) { \ + int _r; \ + if (F_ISSET(D, DB_AM_LOCKING) && !F_ISSET(D, DB_AM_RECOVER)) { \ + (D)->lock.pgno = BUCKET_INVALID; \ + if ((_r = lock_get((D)->dbenv->lk_info, \ + (D)->txn == NULL ? (D)->locker : (D)->txn->txnid, \ + 0, &(D)->lock_dbt, DB_LOCK_READ, \ + &(H)->hlock)) != 0) \ + return (_r < 0 ? EAGAIN : _r); \ + } \ + if ((_r = __ham_get_page(D, 0, (PAGE **)&((H)->hdr))) != 0) { \ + if ((H)->hlock) { \ + (void)lock_put((D)->dbenv->lk_info, (H)->hlock);\ + (H)->hlock = 0; \ + } \ + return (_r); \ + } \ +} + +#define RELEASE_META(D, H) { \ + if (!F_ISSET(D, DB_AM_RECOVER) && \ + (D)->txn == NULL && (H)->hlock) \ + (void)lock_put((H)->dbp->dbenv->lk_info, (H)->hlock); \ + (H)->hlock = 0; \ + if ((H)->hdr) \ + (void)__ham_put_page(D, (PAGE *)(H)->hdr, \ + F_ISSET(D, DB_HS_DIRTYMETA) ? 1 : 0); \ + (H)->hdr = NULL; \ + F_CLR(D, DB_HS_DIRTYMETA); \ +} + +#define DIRTY_META(H, R) { \ + if (F_ISSET((H)->dbp, DB_AM_LOCKING) && \ + !F_ISSET((H)->dbp, DB_AM_RECOVER)) { \ + DB_LOCK _tmp; \ + (H)->dbp->lock.pgno = BUCKET_INVALID; \ + if (((R) = lock_get((H)->dbp->dbenv->lk_info, \ + (H)->dbp->txn ? (H)->dbp->txn->txnid : \ + (H)->dbp->locker, 0, &(H)->dbp->lock_dbt, \ + DB_LOCK_WRITE, &_tmp)) == 0) \ + (R) = lock_put((H)->dbp->dbenv->lk_info, \ + (H)->hlock); \ + else if ((R) < 0) \ + (R) = EAGAIN; \ + (H)->hlock = _tmp; \ + } \ + F_SET((H)->dbp, DB_HS_DIRTYMETA); \ +} + +/* Allocate and discard thread structures. */ +#define H_GETHANDLE(dbp, dbpp, ret) \ + if (F_ISSET(dbp, DB_AM_THREAD)) \ + ret = __db_gethandle(dbp, __ham_hdup, dbpp); \ + else { \ + ret = 0; \ + *dbpp = dbp; \ + } + +#define H_PUTHANDLE(dbp) { \ + if (F_ISSET(dbp, DB_AM_THREAD)) \ + __db_puthandle(dbp); \ +} + +/* Test string. */ +#define CHARKEY "%$sniglet^&" + +/* Overflow management */ +/* + * Overflow page numbers are allocated per split point. At each doubling of + * the table, we can allocate extra pages. We keep track of how many pages + * we've allocated at each point to calculate bucket to page number mapping. + */ +#define BUCKET_TO_PAGE(H, B) \ + ((B) + 1 + ((B) ? (H)->hdr->spares[__db_log2((B)+1)-1] : 0)) + +#define PGNO_OF(H, S, O) (BUCKET_TO_PAGE((H), (1 << (S)) - 1) + (O)) + +/* Constraints about number of pages and how much data goes on a page. */ + +#define MAX_PAGES(H) UINT32_T_MAX +#define MINFILL 0.25 +#define ISBIG(H, N) (((N) > ((H)->hdr->pagesize * MINFILL)) ? 1 : 0) + +/* Shorthands for accessing structure */ +#define NDX_INVALID 0xFFFF +#define BUCKET_INVALID 0xFFFFFFFF + +/* On page duplicates are stored as a string of size-data-size triples. */ +#define DUP_SIZE(len) ((len) + 2 * sizeof(db_indx_t)) + +/* Log messages types (these are subtypes within a record type) */ +#define PAIR_KEYMASK 0x1 +#define PAIR_DATAMASK 0x2 +#define PAIR_ISKEYBIG(N) (N & PAIR_KEYMASK) +#define PAIR_ISDATABIG(N) (N & PAIR_DATAMASK) +#define OPCODE_OF(N) (N & ~(PAIR_KEYMASK | PAIR_DATAMASK)) + +#define PUTPAIR 0x20 +#define DELPAIR 0x30 +#define PUTOVFL 0x40 +#define DELOVFL 0x50 +#define ALLOCPGNO 0x60 +#define DELPGNO 0x70 +#define SPLITOLD 0x80 +#define SPLITNEW 0x90 + +#include "hash_auto.h" +#include "hash_ext.h" +#include "db_am.h" +#include "common_ext.h" |