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/*-
* See the file LICENSE for redistribution information.
*
* Copyright (c) 1996, 1997, 1998, 1999
* Sleepycat Software. All rights reserved.
*
* @(#)txn.h 11.4 (Sleepycat) 10/12/99
*/
#ifndef _TXN_H_
#define _TXN_H_
#include "xa.h"
struct __db_txnmgr; typedef struct __db_txnmgr DB_TXNMGR;
struct __db_txnregion; typedef struct __db_txnregion DB_TXNREGION;
/*
* !!!
* TXN_MINIMUM = (DB_LOCK_MAXID + 1) but this makes compilers complain.
*/
#define TXN_MINIMUM 0x80000000
#define TXN_INVALID 0xffffffff /* Maximum number of txn ids. */
#define TXN_INVALID_ID 0 /* Invalid transaction ID. */
#define DEF_MAX_TXNS 20 /* Default max transactions. */
/* The structure allocated for every transaction. */
struct __db_txn {
DB_TXNMGR *mgrp; /* Pointer to transaction manager. */
DB_TXN *parent; /* Pointer to transaction's parent. */
DB_LSN last_lsn; /* Lsn of last log write. */
u_int32_t txnid; /* Unique transaction id. */
roff_t off; /* Detail structure within region. */
TAILQ_ENTRY(__db_txn) links; /* Links transactions off manager. */
TAILQ_HEAD(__kids, __db_txn) kids; /* Child transactions. */
TAILQ_ENTRY(__db_txn) klinks; /* Links child transactions. */
#define TXN_CHILDCOMMIT 0x01 /* Transaction that has committed. */
#define TXN_MALLOC 0x02 /* Structure allocated by TXN system. */
#define TXN_MUSTFLUSH 0x04 /* A child has committed. */
#define TXN_NOSYNC 0x08 /* Do not sync on prepare and commit. */
#define TXN_NOWAIT 0x10 /* Do not wait on locks. */
#define TXN_SYNC 0x20 /* Sync on prepare and commit. */
u_int32_t flags;
};
/*
* Internal data maintained in shared memory for each transaction.
*/
typedef char DB_XID[XIDDATASIZE];
typedef struct __txn_detail {
u_int32_t txnid; /* current transaction id
used to link free list also */
DB_LSN last_lsn; /* last lsn written for this txn */
DB_LSN begin_lsn; /* lsn of begin record */
roff_t parent; /* Offset of transaction's parent. */
#define TXN_UNALLOC 0
#define TXN_RUNNING 1
#define TXN_ABORTED 2
#define TXN_PREPARED 3
#define TXN_COMMITTED 4
u_int32_t status; /* status of the transaction */
SH_TAILQ_ENTRY links; /* free/active list */
#define TXN_XA_ABORTED 1
#define TXN_XA_DEADLOCKED 2
#define TXN_XA_ENDED 3
#define TXN_XA_PREPARED 4
#define TXN_XA_STARTED 5
#define TXN_XA_SUSPENDED 6
u_int32_t xa_status; /* XA status */
/*
* XID (xid_t) structure: because these fields are logged, the
* sizes have to be explicit.
*/
DB_XID xid; /* XA global transaction id */
u_int32_t bqual; /* bqual_length from XID */
u_int32_t gtrid; /* gtrid_length from XID */
int32_t format; /* XA format */
} TXN_DETAIL;
/*
* DB_TXNMGR --
* The transaction manager encapsulates the transaction system.
*/
struct __db_txnmgr {
/*
* These fields need to be protected for multi-threaded support.
*
* !!!
* As this structure is allocated in per-process memory, the mutex may need
* to be stored elsewhere on architectures unable to support mutexes in heap
* memory, e.g., HP/UX 9.
*/
MUTEX *mutexp; /* Lock list of active transactions
* (including the content of each
* TXN_DETAIL structure on the list).
*/
/* List of active transactions. */
TAILQ_HEAD(_chain, __db_txn) txn_chain;
/* These fields are never updated after creation, and so not protected. */
DB_ENV *dbenv; /* Environment. */
REGINFO reginfo; /* Region information. */
int (*recover) /* Recovery dispatch routine */
__P((DB_ENV *, DBT *, DB_LSN *, int, void *));
};
/*
* DB_TXNREGION --
* The primary transaction data structure in the shared memory region.
*/
struct __db_txnregion {
u_int32_t maxtxns; /* maximum number of active TXNs */
u_int32_t last_txnid; /* last transaction id given out */
DB_LSN pending_ckp; /* last checkpoint did not finish */
DB_LSN last_ckp; /* lsn of the last checkpoint */
time_t time_ckp; /* time of last checkpoint */
u_int32_t logtype; /* type of logging */
u_int32_t locktype; /* lock type */
u_int32_t naborts; /* number of aborted TXNs */
u_int32_t ncommits; /* number of committed TXNs */
u_int32_t nbegins; /* number of begun TXNs */
u_int32_t nactive; /* number of active TXNs */
u_int32_t maxnactive; /* maximum number of active TXNs */
/* active TXN list */
SH_TAILQ_HEAD(__active) active_txn;
};
/*
* Make the region large enough to hold N transaction detail structures
* plus some space to hold thread handles and the beginning of the shalloc
* region.
*/
#define TXN_REGION_SIZE(N) \
(sizeof(DB_TXNREGION) + N * sizeof(TXN_DETAIL) + 1000)
/*
* Log record types.
*/
#define TXN_COMMIT 1
#define TXN_PREPARE 2
#define TXN_CHECKPOINT 3
#include "txn_auto.h"
#include "txn_ext.h"
#include "xa_ext.h"
#endif /* !_TXN_H_ */