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Diffstat (limited to 'bdb/dbinc/hash.h')
| -rw-r--r-- | bdb/dbinc/hash.h | 147 |
1 files changed, 147 insertions, 0 deletions
diff --git a/bdb/dbinc/hash.h b/bdb/dbinc/hash.h new file mode 100644 index 00000000000..98289735fc4 --- /dev/null +++ b/bdb/dbinc/hash.h @@ -0,0 +1,147 @@ +/*- + * See the file LICENSE for redistribution information. + * + * Copyright (c) 1996-2002 + * 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. 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. + * + * $Id: hash.h,v 11.26 2002/03/27 04:34:54 bostic Exp $ + */ + +#ifndef _DB_HASH_H_ +#define _DB_HASH_H_ + +/* Hash internal structure. */ +typedef struct hash_t { + db_pgno_t meta_pgno; /* Page number of the meta data page. */ + u_int32_t h_ffactor; /* Fill factor. */ + u_int32_t h_nelem; /* Number of elements. */ + /* Hash function. */ + u_int32_t (*h_hash) __P((DB *, const void *, u_int32_t)); +} HASH; + +/* Cursor structure definitions. */ +typedef struct cursor_t { + /* struct __dbc_internal */ + __DBC_INTERNAL + + /* Hash private part */ + + /* Per-thread information */ + DB_LOCK hlock; /* Metadata page lock. */ + HMETA *hdr; /* Pointer to meta-data page. */ + PAGE *split_buf; /* Temporary buffer for splits. */ + + /* Hash cursor information */ + db_pgno_t bucket; /* Bucket we are traversing. */ + db_pgno_t lbucket; /* Bucket for which we are locked. */ + 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 order; /* Relative order among deleted curs. */ + +#define H_CONTINUE 0x0001 /* Join--search strictly fwd for data */ +#define H_DELETED 0x0002 /* Cursor item is deleted. */ +#define H_DIRTY 0x0004 /* Meta-data page needs to be written */ +#define H_DUPONLY 0x0008 /* Dups only; do not change key. */ +#define H_EXPAND 0x0010 /* Table expanded. */ +#define H_ISDUP 0x0020 /* Cursor is within duplicate set. */ +#define H_NEXT_NODUP 0x0040 /* Get next non-dup entry. */ +#define H_NOMORE 0x0080 /* No more entries in bucket. */ +#define H_OK 0x0100 /* Request succeeded. */ + u_int32_t flags; +} HASH_CURSOR; + +/* Test string. */ +#define CHARKEY "%$sniglet^&" + +/* Overflow management */ +/* + * The spares table indicates the page number at which each doubling begins. + * From this page number we subtract the number of buckets already allocated + * so that we can do a simple addition to calculate the page number here. + */ +#define BS_TO_PAGE(bucket, spares) \ + ((bucket) + (spares)[__db_log2((bucket) + 1)]) +#define BUCKET_TO_PAGE(I, B) (BS_TO_PAGE((B), (I)->hdr->spares)) + +/* Constraints about much data goes on a page. */ + +#define MINFILL 4 +#define ISBIG(I, N) (((N) > ((I)->hdr->dbmeta.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_DUPMASK 0x4 +#define PAIR_MASK 0xf +#define PAIR_ISKEYBIG(N) (N & PAIR_KEYMASK) +#define PAIR_ISDATABIG(N) (N & PAIR_DATAMASK) +#define PAIR_ISDATADUP(N) (N & PAIR_DUPMASK) +#define OPCODE_OF(N) (N & ~PAIR_MASK) + +#define PUTPAIR 0x20 +#define DELPAIR 0x30 +#define PUTOVFL 0x40 +#define DELOVFL 0x50 +#define HASH_UNUSED1 0x60 +#define HASH_UNUSED2 0x70 +#define SPLITOLD 0x80 +#define SPLITNEW 0x90 + +typedef enum { + DB_HAM_CHGPG = 1, + DB_HAM_DELFIRSTPG = 2, + DB_HAM_DELMIDPG = 3, + DB_HAM_DELLASTPG = 4, + DB_HAM_DUP = 5, + DB_HAM_SPLIT = 6 +} db_ham_mode; + +#include "dbinc_auto/hash_auto.h" +#include "dbinc_auto/hash_ext.h" +#include "dbinc/db_am.h" +#endif /* !_DB_HASH_H_ */ |