stasis-aries-wal/lladd/logger/logger2.h

142 lines
4.5 KiB
C

/*---
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authorized uses. Modifications to this software may be copyrighted by
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provided that the new terms are clearly indicated on the first page of
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FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
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POSSIBILITY OF SUCH DAMAGE.
THE AUTHORS AND DISTRIBUTORS SPECIFICALLY DISCLAIM ANY WARRANTIES,
INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, AND
NON-INFRINGEMENT. THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, AND
THE AUTHORS AND DISTRIBUTORS HAVE NO OBLIGATION TO PROVIDE
MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
GOVERNMENT USE: If you are acquiring this software on behalf of the
U.S. government, the Government shall have only "Restricted Rights" in
the software and related documentation as defined in the Federal
Acquisition Regulations (FARs) in Clause 52.227.19 (c) (2). If you are
acquiring the software on behalf of the Department of Defense, the
software shall be classified as "Commercial Computer Software" and the
Government shall have only "Restricted Rights" as defined in Clause
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authors grant the U.S. Government and others acting in its behalf
permission to use and distribute the software in accordance with the
terms specified in this license.
---*/
/**
* @file
*
* New version of logger. Based on logger.h
*
* $Id$
*
*/
#ifndef __LOGGER2_H__
#define __LOGGER2_H__
#include <lladd/operations.h>
/**
A callback function that allows logHandle's iterator to stop
returning log entries depending on the context in which it was
called.
*/
typedef int (guard_fcn_t)(LogEntry *, void *);
typedef struct {
/** The LSN of the last log entry returned.*/
/* lsn_t file_offset; */ /* Unneeded? */
/** The LSN of the log entry that we would return if next is called. */
lsn_t next_offset;
/** The LSN of the log entry that we would return if previous is called. */
lsn_t prev_offset;
guard_fcn_t * guard;
void * guard_state;
} LogHandle;
/**
Contains the state needed by the logging layer to perform
operations on a transaction.
*/
typedef struct {
int xid;
lsn_t prevLSN;
LogHandle lh;
} TransactionLog;
/**
Inform the logging layer that a new transaction has begun.
Currently a no-op.
*/
TransactionLog LogTransBegin(int xid);
/**
Write a transaction COMMIT to the log tail, then flush the log tail immediately to disk
@return The lsn of the commit log entry.
*/
lsn_t LogTransCommit(TransactionLog * l);
/**
Write a transaction ABORT to the log tail
@return The lsn of the abort log entry.
*/
lsn_t LogTransAbort(TransactionLog * l);
/**
LogUpdate writes an UPDATE log record to the log tail
*/
LogEntry * LogUpdate(TransactionLog * l, recordid rid, int operation, const byte * args);
/* *
(Was folded into LogUpdate.)
Logs the fact that a rid has been allocated for a transaction.
@ todo Should this be folded into LogUpdate? (Make "alloc" an operation...)
@ todo Surely, we need a dealloc!
*/
/*lsn_t LogTransAlloc(TransactionLog * l, recordid rid);*/
/**
Write a compensation log record. These records are used to allow
for efficient recovery, and possibly for log truncation. They
record the completion of undo operations.
@return the lsn of the CLR entry that was written to the log.
(Needed so that the lsn slot of the page in question can be
updated.)
@todo Remove this from this interface? Should it be internal to
the recovery routines?
*/
lsn_t LogCLR (LogEntry * undone); /*TransactionLog * l, long ulLSN, recordid ulRID, long ulPrevLSN); */
/**
Write a end transaction record @see XEND
@todo Implement LogEnd
*/
void LogEnd (TransactionLog * l);
#endif