gecko-dev/db/hash/hash.src
1998-10-15 03:56:37 +00:00

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/*-
* See the file LICENSE for redistribution information.
*
* Copyright (c) 1996, 1997, 1998
* Sleepycat Software. All rights reserved.
*/
/*
* Copyright (c) 1995, 1996
* Margo Seltzer. All rights reserved.
*/
/*
* Copyright (c) 1995, 1996
* The President and Fellows of Harvard University. 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.src 10.3 (Sleepycat) 4/10/98
*/
/*
* This is the source file used to create the logging functions for the
* hash package. Each access method (or set of routines wishing to register
* record types with the transaction system) should have a file like this.
* Each type of log record and its parameters is defined. The basic
* format of a record definition is:
*
* BEGIN <RECORD_TYPE>
* ARG|STRING|POINTER <variable name> <variable type> <printf format>
* ...
* END
* ARG the argument is a simple parameter of the type * specified.
* DBT the argument is a DBT (db.h) containing a length and pointer.
* PTR the argument is a pointer to the data type specified; the entire
* type should be logged.
*
* There are a set of shell scripts of the form xxx.sh that generate c
* code and or h files to process these. (This is probably better done
* in a single PERL script, but for now, this works.)
*
* The DB recovery system requires the following three fields appear in
* every record, and will assign them to the per-record-type structures
* as well as making them the first parameters to the appropriate logging
* call.
* rectype: record-type, identifies the structure and log/read call
* txnid: transaction id, a DBT in this implementation
* prev: the last LSN for this transaction
*/
/*
* Use the argument of PREFIX as the prefix for all record types,
* routines, id numbers, etc.
*/
PREFIX ham
/*
* HASH-insdel: used for hash to insert/delete a pair of entries onto a master
* page. The pair might be regular key/data pairs or they might be the
* structures that refer to off page items, duplicates or offpage duplicates.
* opcode - PUTPAIR/DELPAIR + big masks
* fileid - identifies the file referenced
* pgno - page within file
* ndx - index on the page of the item being added (item index)
* pagelsn - lsn on the page before the update
* key - the key being inserted
* data - the data being inserted
*/
BEGIN insdel
ARG opcode u_int32_t lu
ARG fileid u_int32_t lu
ARG pgno db_pgno_t lu
ARG ndx u_int32_t lu
POINTER pagelsn DB_LSN * lu
DBT key DBT s
DBT data DBT s
END
/*
* Used to add and remove overflow pages.
* prev_pgno is the previous page that is going to get modified to
* point to this one. If this is the first page in a chain
* then prev_pgno should be PGNO_INVALID.
* new_pgno is the page being allocated.
* next_pgno is the page that follows this one. On allocation,
* this should be PGNO_INVALID. For deletes, it may exist.
* pagelsn is the old lsn on the page.
*/
BEGIN newpage
ARG opcode u_int32_t lu
ARG fileid u_int32_t lu
ARG prev_pgno db_pgno_t lu
POINTER prevlsn DB_LSN * lu
ARG new_pgno db_pgno_t lu
POINTER pagelsn DB_LSN * lu
ARG next_pgno db_pgno_t lu
POINTER nextlsn DB_LSN * lu
END
/*
* Splitting requires two types of log messages. The first
* logs the meta-data of the split. The second logs the
* data on the original page. To redo the split, we have
* to visit the new page (pages) and add the items back
* on the page if they are not yet there.
* For the meta-data split
* bucket: max_bucket in table before split
* ovflpoint: overflow point before split.
* spares: spares[ovflpoint] before split.
*/
BEGIN splitmeta
ARG fileid u_int32_t lu
ARG bucket u_int32_t lu
ARG ovflpoint u_int32_t lu
ARG spares u_int32_t lu
POINTER metalsn DB_LSN * lu
END
BEGIN splitdata
ARG fileid u_int32_t lu
ARG opcode u_int32_t lu
ARG pgno db_pgno_t lu
DBT pageimage DBT s
POINTER pagelsn DB_LSN * lu
END
/*
* HASH-replace: is used for hash to handle partial puts that only
* affect a single master page.
* fileid - identifies the file referenced
* pgno - page within file
* ndx - index on the page of the item being modified (item index)
* pagelsn - lsn on the page before the update
* off - offset in the old item where the new item is going.
* olditem - DBT that describes the part of the item being replaced.
* newitem - DBT of the new item.
* makedup - this was a replacement that made an item a duplicate.
*/
BEGIN replace
ARG fileid u_int32_t lu
ARG pgno db_pgno_t lu
ARG ndx u_int32_t lu
POINTER pagelsn DB_LSN * lu
ARG off int32_t ld
DBT olditem DBT s
DBT newitem DBT s
ARG makedup u_int32_t lu
END
/*
* HASH-newpgno: is used to record getting/deleting a new page number.
* This doesn't require much data modification, just modifying the
* meta-data.
* pgno is the page being allocated/freed.
* free_pgno is the next_pgno on the free list.
* old_type was the type of a page being deallocated.
* old_pgno was the next page number before the deallocation. We use it
* to indicate whether we incremented the spares count or not
* during this allocation.
*/
BEGIN newpgno
ARG opcode u_int32_t lu
ARG fileid u_int32_t lu
ARG pgno db_pgno_t lu
ARG free_pgno db_pgno_t lu
ARG old_type u_int32_t lu
ARG old_pgno db_pgno_t lu
ARG new_type u_int32_t lu
POINTER pagelsn DB_LSN * lu
POINTER metalsn DB_LSN * lu
END
/*
* ovfl: initialize a set of overflow pages.
*/
BEGIN ovfl
ARG fileid u_int32_t lu
ARG start_pgno db_pgno_t lu
ARG npages u_int32_t lu
ARG free_pgno db_pgno_t lu
ARG ovflpoint u_int32_t lu
POINTER metalsn DB_LSN * lu
END
/*
* Used when we empty the first page in a bucket and there are pages
* after it. The page after it gets copied into the bucket page (since
* bucket pages have to be in fixed locations).
* pgno: the bucket page
* pagelsn: the old LSN on the bucket page
* next_pgno: the page number of the next page
* nnext_pgno: page after next_pgno (may need to change its prev)
* nnextlsn: the LSN of nnext_pgno.
*/
BEGIN copypage
ARG fileid u_int32_t lu
ARG pgno db_pgno_t lu
POINTER pagelsn DB_LSN * lu
ARG next_pgno db_pgno_t lu
POINTER nextlsn DB_LSN * lu
ARG nnext_pgno db_pgno_t lu
POINTER nnextlsn DB_LSN * lu
DBT page DBT s
END