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2ff501590b
Also performed an initial run through of upgrading our Copyright date to extend to 2005 ... first run here was very simple ... change everything where: grep 1996-2004 && the word 'Copyright' ... scanned through the generated list with 'less' first, and after, to make sure that I only picked up the right entries ...
66 lines
2.3 KiB
C
66 lines
2.3 KiB
C
/*
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* xlogdefs.h
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*
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* Postgres transaction log manager record pointer and
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* timeline number definitions
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*
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* Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
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* Portions Copyright (c) 1994, Regents of the University of California
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*
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* $PostgreSQL: pgsql/src/include/access/xlogdefs.h,v 1.14 2004/12/31 22:03:21 pgsql Exp $
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*/
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#ifndef XLOG_DEFS_H
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#define XLOG_DEFS_H
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/*
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* Pointer to a location in the XLOG. These pointers are 64 bits wide,
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* because we don't want them ever to overflow.
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*
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* NOTE: xrecoff == 0 is used to indicate an invalid pointer. This is OK
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* because we use page headers in the XLOG, so no XLOG record can start
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* right at the beginning of a file.
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*
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* NOTE: the "log file number" is somewhat misnamed, since the actual files
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* making up the XLOG are much smaller than 4Gb. Each actual file is an
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* XLogSegSize-byte "segment" of a logical log file having the indicated
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* xlogid. The log file number and segment number together identify a
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* physical XLOG file. Segment number and offset within the physical file
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* are computed from xrecoff div and mod XLogSegSize.
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*/
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typedef struct XLogRecPtr
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{
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uint32 xlogid; /* log file #, 0 based */
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uint32 xrecoff; /* byte offset of location in log file */
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} XLogRecPtr;
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/*
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* Macros for comparing XLogRecPtrs
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*
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* Beware of passing expressions with side-effects to these macros,
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* since the arguments may be evaluated multiple times.
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*/
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#define XLByteLT(a, b) \
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((a).xlogid < (b).xlogid || \
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((a).xlogid == (b).xlogid && (a).xrecoff < (b).xrecoff))
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#define XLByteLE(a, b) \
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((a).xlogid < (b).xlogid || \
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((a).xlogid == (b).xlogid && (a).xrecoff <= (b).xrecoff))
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#define XLByteEQ(a, b) \
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((a).xlogid == (b).xlogid && (a).xrecoff == (b).xrecoff)
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/*
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* TimeLineID (TLI) - identifies different database histories to prevent
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* confusion after restoring a prior state of a database installation.
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* TLI does not change in a normal stop/restart of the database (including
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* crash-and-recover cases); but we must assign a new TLI after doing
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* a recovery to a prior state, a/k/a point-in-time recovery. This makes
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* the new WAL logfile sequence we generate distinguishable from the
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* sequence that was generated in the previous incarnation.
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*/
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typedef uint32 TimeLineID;
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#endif /* XLOG_DEFS_H */
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