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/*
*
* xlog.h
*
* Postgres transaction log manager
*
*/
#ifndef XLOG_H
#define XLOG_H
#include "access/rmgr.h"
#include "access/transam.h"
#include "access/xlogdefs.h"
typedef struct XLogRecord
{
XLogRecPtr xl_prev; /* ptr to previous record in log */
XLogRecPtr xl_xact_prev; /* ptr to previous record of this xact */
TransactionId xl_xid; /* xact id */
uint16 xl_len; /* len of record *data* on this page */
uint8 xl_info;
RmgrId xl_rmid; /* resource manager inserted this record */
/* ACTUAL LOG DATA FOLLOWS AT END OF STRUCT */
} XLogRecord;
#define SizeOfXLogRecord DOUBLEALIGN(sizeof(XLogRecord))
#define MAXLOGRECSZ (2 * BLCKSZ)
#define XLogRecGetData(record) \
((char*)record + SizeOfXLogRecord)
/*
* When there is no space on current page we continue on the next
* page with subrecord.
*/
typedef struct XLogSubRecord
{
uint16 xl_len;
uint8 xl_info;
/* ACTUAL LOG DATA FOLLOWS AT END OF STRUCT */
} XLogSubRecord;
#define SizeOfXLogSubRecord DOUBLEALIGN(sizeof(XLogSubRecord))
/*
* XLOG uses only low 4 bits of xl_info. High 4 bits may be used
* by rmgr...
*/
#define XLR_TO_BE_CONTINUED 0x01
#define XLR_INFO_MASK 0x0F
#define XLOG_PAGE_MAGIC 0x17345168
typedef struct XLogPageHeaderData
{
uint32 xlp_magic;
uint16 xlp_info;
} XLogPageHeaderData;
#define SizeOfXLogPHD DOUBLEALIGN(sizeof(XLogPageHeaderData))
typedef XLogPageHeaderData *XLogPageHeader;
#define XLP_FIRST_IS_SUBRECORD 0x0001
#define XLByteLT(left, right) \
(right.xlogid > left.xlogid || \
(right.xlogid == left.xlogid && right.xrecoff > left.xrecoff))
#define XLByteLE(left, right) \
(right.xlogid > left.xlogid || \
(right.xlogid == left.xlogid && right.xrecoff >= left.xrecoff))
#define XLByteEQ(left, right) \
(right.xlogid == left.xlogid && right.xrecoff == left.xrecoff)
extern StartUpID ThisStartUpID; /* current SUI */
extern bool InRecovery;
extern XLogRecPtr MyLastRecPtr;
typedef struct RmgrData
{
char *rm_name;
void (*rm_redo)(XLogRecPtr lsn, XLogRecord *rptr);
void (*rm_undo)(XLogRecPtr lsn, XLogRecord *rptr);
void (*rm_desc)(char *buf, uint8 xl_info, char *rec);
} RmgrData;
extern RmgrData RmgrTable[];
extern XLogRecPtr XLogInsert(RmgrId rmid, uint8 info,
char *hdr, uint32 hdrlen,
char *buf, uint32 buflen);
extern void XLogFlush(XLogRecPtr RecPtr);
extern void CreateCheckPoint(bool shutdown);
#endif /* XLOG_H */
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