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57 lines
1.5 KiB
C
57 lines
1.5 KiB
C
/*-------------------------------------------------------------------------
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*
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* lselect.h
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* definitions for the replacement selection algorithm.
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*
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*
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* Copyright (c) 1994, Regents of the University of California
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*
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* $Id: lselect.h,v 1.12 1999/02/13 23:22:24 momjian Exp $
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*
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*-------------------------------------------------------------------------
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*/
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#ifndef LSELECT_H
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#define LSELECT_H
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#include <stdio.h>
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#include "access/skey.h"
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#include "access/tupdesc.h"
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#include "access/htup.h"
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#include "utils/syscache.h"
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struct leftist
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{
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short lt_dist; /* distance to leaf/empty node */
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short lt_devnum; /* device number of tuple */
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HeapTuple lt_tuple;
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struct leftist *lt_left;
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struct leftist *lt_right;
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};
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/* replaces global variables in lselect.c to make it reentrant */
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typedef struct
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{
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TupleDesc tupDesc;
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int nKeys;
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ScanKey scanKeys;
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int sortMem; /* needed for psort */
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} LeftistContextData;
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typedef LeftistContextData *LeftistContext;
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extern struct leftist *lmerge(struct leftist * pt, struct leftist * qt,
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LeftistContext context);
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extern HeapTuple gettuple(struct leftist ** treep, short *devnum,
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LeftistContext context);
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extern void puttuple(struct leftist ** treep, HeapTuple newtuple, short devnum,
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LeftistContext context);
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extern int tuplecmp(HeapTuple ltup, HeapTuple rtup, LeftistContext context);
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#ifdef EBUG
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extern void checktree(struct leftist * tree, LeftistContext context);
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extern int checktreer(struct leftist * tree, int level, LeftistContext context);
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#endif /* EBUG */
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#endif /* LSELECT_H */
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