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Diffstat (limited to 'db2/include/txn.h')
| -rw-r--r-- | db2/include/txn.h | 112 |
1 files changed, 112 insertions, 0 deletions
diff --git a/db2/include/txn.h b/db2/include/txn.h new file mode 100644 index 0000000000..f4e0999b36 --- /dev/null +++ b/db2/include/txn.h @@ -0,0 +1,112 @@ +/*- + * See the file LICENSE for redistribution information. + * + * Copyright (c) 1996, 1997 + * Sleepycat Software. All rights reserved. + * + * @(#)txn.h 10.6 (Sleepycat) 7/29/97 + */ +#ifndef _TXN_H_ +#define _TXN_H_ + +/* + * The name of the transaction shared memory region is DEFAULT_TXN_FILE and + * the region is always created group RW of the group owning the directory. + */ +#define DEFAULT_TXN_FILE "__db_txn.share" +#define TXN_INVALID 0xffffffff /* Maximum number of txn ids. */ +#define TXN_MINIMUM 0x80000000 /* First transaction id */ + +/* + * Transaction type declarations. + */ + +/* + * Internal data maintained in shared memory for each transaction. + */ +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 */ + size_t last_lock; /* offset in lock region of last lock + for this transaction. */ +#define TXN_UNALLOC 0 +#define TXN_RUNNING 1 +#define TXN_ABORTED 2 +#define TXN_PREPARED 3 + u_int32_t status; /* status of the transaction */ +} TXN_DETAIL; + +/* + * The transaction manager encapsulates the transaction system. It contains + * references to the log and lock managers as well as the state that keeps + * track of the shared memory region. + */ +struct __db_txnmgr { +/* These fields need to be protected for multi-threaded support. */ + db_mutex_t mutex; /* Synchronization. */ + /* list of active transactions */ + TAILQ_HEAD(_chain, __db_txn) txn_chain; + +/* These fields are not protected. */ + DB_ENV *dbenv; /* Environment. */ + int (*recover) /* Recovery dispatch routine */ + __P((DB_LOG *, DBT *, DB_LSN *, int, void *)); + int fd; /* mapped file descriptor */ + u_int flags; /* DB_TXN_NOSYNC, DB_THREAD */ + size_t reg_size; /* how large we think the region is */ + DB_TXNREGION *region; /* address of shared memory region */ +}; + +/* + * Layout of the shared memory region. + * + */ +struct __db_txnregion { + RLAYOUT hdr; /* Shared memory region header. */ + u_int32_t magic; /* transaction magic number */ + u_int32_t version; /* version number */ + u_int32_t maxtxns; /* maximum number of active txns */ + u_int32_t last_txnid; /* last transaction id given out */ + u_int32_t free_txn; /* head of transaction free list */ + 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 transactions */ + u_int32_t ncommits; /* number of committed transactions */ + u_int32_t nbegins; /* number of begun transactions */ + TXN_DETAIL table[1]; /* array of TXN structures */ +}; + +#define TXN_REGION_SIZE(N) \ + (sizeof(DB_TXNREGION) + N * sizeof(DB_TXN)) + +/* Macros to lock/unlock the region and threads. */ +#define LOCK_TXNTHREAD(tmgrp) \ + if (F_ISSET(tmgrp, DB_THREAD)) \ + (void)__db_mutex_lock(&(tmgrp)->mutex, -1, \ + (tmgrp)->dbenv == NULL ? NULL : (tmgrp)->dbenv->db_yield) +#define UNLOCK_TXNTHREAD(tmgrp) \ + if (F_ISSET(tmgrp, DB_THREAD)) \ + (void)__db_mutex_unlock(&(tmgrp)->mutex, -1) + +#define LOCK_TXNREGION(tmgrp) \ + (void)__db_mutex_lock(&(tmgrp)->region->hdr.lock,(tmgrp)->fd, \ + (tmgrp)->dbenv == NULL ? NULL : (tmgrp)->dbenv->db_yield) +#define UNLOCK_TXNREGION(tmgrp) \ + (void)__db_mutex_unlock(&(tmgrp)->region->hdr.lock, (tmgrp)->fd) + +/* + * Log record types. + */ +#define TXN_BEGIN 1 +#define TXN_COMMIT 2 +#define TXN_PREPARE 3 +#define TXN_CHECKPOINT 4 + +#include "txn_auto.h" +#include "txn_ext.h" +#endif /* !_TXN_H_ */ |