src/include/access/clog.h

   1 /*
   2  * clog.h
   3  *
   4  * PostgreSQL transaction-commit-log manager
   5  *
   6  * Portions Copyright (c) 1996-2021, PostgreSQL Global Development Group
   7  * Portions Copyright (c) 1994, Regents of the University of California
   8  *
   9  * src/include/access/clog.h
  10  */
  11 #ifndef CLOG_H
  12 #define CLOG_H
  13
  14 #include "access/xlogreader.h"
  15 #include "storage/sync.h"
  16 #include "lib/stringinfo.h"
  17
  18 /*
  19  * Possible transaction statuses --- note that all-zeroes is the initial
  20  * state.
  21  *
  22  * A "subcommitted" transaction is a committed subtransaction whose parent
  23  * hasn't committed or aborted yet.
  24  */
  25 typedef int XidStatus;
  26
  27 #define TRANSACTION_STATUS_IN_PROGRESS          0x00
  28 #define TRANSACTION_STATUS_COMMITTED            0x01
  29 #define TRANSACTION_STATUS_ABORTED                      0x02
  30 #define TRANSACTION_STATUS_SUB_COMMITTED        0x03
  31
  32 typedef struct xl_clog_truncate
  33 {
  34         int                     pageno;
  35         TransactionId oldestXact;
  36         Oid                     oldestXactDb;
  37 } xl_clog_truncate;
  38
  39 extern void TransactionIdSetTreeStatus(TransactionId xid, int nsubxids,
  40                                                                            TransactionId *subxids, XidStatus status, XLogRecPtr lsn);
  41 extern XidStatus TransactionIdGetStatus(TransactionId xid, XLogRecPtr *lsn);
  42
  43 extern Size CLOGShmemBuffers(void);
  44 extern Size CLOGShmemSize(void);
  45 extern void CLOGShmemInit(void);
  46 extern void BootStrapCLOG(void);
  47 extern void StartupCLOG(void);
  48 extern void TrimCLOG(void);
  49 extern void CheckPointCLOG(void);
  50 extern void ExtendCLOG(TransactionId newestXact);
  51 extern void TruncateCLOG(TransactionId oldestXact, Oid oldestxid_datoid);
  52
  53 extern int      clogsyncfiletag(const FileTag *ftag, char *path);
  54
  55 /* XLOG stuff */
  56 #define CLOG_ZEROPAGE           0x00
  57 #define CLOG_TRUNCATE           0x10
  58
  59 extern void clog_redo(XLogReaderState *record);
  60 extern void clog_desc(StringInfo buf, XLogReaderState *record);
  61 extern const char *clog_identify(uint8 info);
  62
  63 #endif                                                  /* CLOG_H */