src/include/access/clog.h

   1 /*
   2  * clog.h
   3  *
   4  * PostgreSQL transaction-commit-log manager
   5  *
   6  * Portions Copyright (c) 1996-2009, PostgreSQL Global Development Group
   7  * Portions Copyright (c) 1994, Regents of the University of California
   8  *
   9  * $PostgreSQL$
  10  */
  11 #ifndef CLOG_H
  12 #define CLOG_H
  13
  14 #include "access/xlog.h"
  15
  16 /*
  17  * Possible transaction statuses --- note that all-zeroes is the initial
  18  * state.
  19  *
  20  * A "subcommitted" transaction is a committed subtransaction whose parent
  21  * hasn't committed or aborted yet.
  22  */
  23 typedef int XidStatus;
  24
  25 #define TRANSACTION_STATUS_IN_PROGRESS          0x00
  26 #define TRANSACTION_STATUS_COMMITTED            0x01
  27 #define TRANSACTION_STATUS_ABORTED                      0x02
  28 #define TRANSACTION_STATUS_SUB_COMMITTED        0x03
  29
  30
  31 /* Number of SLRU buffers to use for clog */
  32 #define NUM_CLOG_BUFFERS        8
  33
  34
  35 extern void TransactionIdSetTreeStatus(TransactionId xid, int nsubxids,
  36                                    TransactionId *subxids, XidStatus status, XLogRecPtr lsn);
  37 extern XidStatus TransactionIdGetStatus(TransactionId xid, XLogRecPtr *lsn);
  38
  39 extern Size CLOGShmemSize(void);
  40 extern void CLOGShmemInit(void);
  41 extern void BootStrapCLOG(void);
  42 extern void StartupCLOG(void);
  43 extern void ShutdownCLOG(void);
  44 extern void CheckPointCLOG(void);
  45 extern void ExtendCLOG(TransactionId newestXact);
  46 extern void TruncateCLOG(TransactionId oldestXact);
  47
  48 /* XLOG stuff */
  49 #define CLOG_ZEROPAGE           0x00
  50 #define CLOG_TRUNCATE           0x10
  51
  52 extern void clog_redo(XLogRecPtr lsn, XLogRecord *record);
  53 extern void clog_desc(StringInfo buf, uint8 xl_info, char *rec);
  54
  55 #endif   /* CLOG_H */