windows-nt/Source/XPSP1/NT/net/jet500/jet/dae/inc/page.h

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2020-09-26 03:20:57 -05:00
//
//------ Page Structure ---------------------------------------------------
//
#define cbPage 4096 // database logical page size
#define cbSec 4096 // minimum disk Read/Write unit. It
// should be 512, but MIPS NT cache
// bug force it be 1024.
#define ctagMax 256 // default limit on number of tags
#define fNoTagLimit (1<<0) // ignore limit on number of tags
#define fUseNewTag (1<<1) // don't reuse tags
typedef BYTE PGTYP;
// the pragma is bad for efficiency, but we need it here so that the
// THREEBYTES will not be aligned on 4-byte boundary
#pragma pack(1)
typedef struct _pghdr
{
ULONG ulChecksum; // checksum of page, always 1st byte
ULONG ulDBTime; // dbCounter when page was dirtied
PGNO pgnoFDP; // pgno of FDP which owns this page
SHORT cbFreeTotal; // total free bytes
SHORT ibLastUsed; // lower bound on used bytes
SHORT ctagMac; // upper bound on used tags
SHORT itagFree; // start of tag free tags
SHORT cVersion; // count of nodes with fVersion flag set
THREEBYTES pgnoPrev; // pgno of previous page
THREEBYTES pgnoNext; // pgno of next page
} PGHDR;
typedef struct _pgtrlr
{
PGTYP pgtyp;
THREEBYTES pgnoThisPage;
} PGTRLR;
typedef struct _tag
{
SHORT cb;
SHORT ib;
} TAG;
/* tag status
/**/
typedef enum { tsLine, tsVacant, tsLink } TS;
typedef struct _page
{
PGHDR pghdr;
TAG rgtag[1];
BYTE rgbFiller[ cbPage -
sizeof(PGHDR) - // pghdr
sizeof(TAG) - // rgtag[1]
sizeof(BYTE) - // rgbData[1]
sizeof(PGTYP) - // pgtyp
sizeof(THREEBYTES) ]; // pgnoThisPage
BYTE rgbData[1];
PGTYP pgtyp;
THREEBYTES pgnoThisPage;
} PAGE;
#pragma pack()
#define bitModified (1<<7)
#define bitLink (1L<<31)
#define pgtypFDP ((PGTYP) 0)
#define pgtypRecord ((PGTYP) 1)
// #define pgtypLong ((PGTYP) 2)
// #define pgtypNonrecord ((PGTYP) 3)
#define pgtypSort ((PGTYP) 4)
#define PMSetPageType( ppage, pgtypT ) ( (ppage)->pgtyp = pgtypT )
#define PgtypPMPageTypeOfPage( ppage ) ((PGTYP)((ppage)->pgtyp & ~(bitModified)))
#ifdef DEBUG
VOID PMSetModified( SSIB *ssib );
VOID PMResetModified( SSIB *pssib );
VOID CheckPgno( PAGE *ppage, PN pn );
#else
#define CheckPgno( ppage, pn )
#define PMSetModified( pssib ) ( (pssib)->pbf->ppage->pgtyp |= bitModified )
#define PMResetModified( pssib ) ( (pssib)->pbf->ppage->pgtyp &= ~(bitModified) )
#endif
#define PgtypPMSetModified( ppage ) ( (ppage)->pgtyp | bitModified )
#define FPMModified( ppage ) ( (ppage)->pgtyp & bitModified )
#define PMSetPgnoFDP( ppage, pgnoT ) ( (ppage)->pghdr.pgnoFDP = pgnoT )
#define PgnoPMPgnoFDPOfPage( ppage ) ( (ppage)->pghdr.pgnoFDP )
#define PMIncVersion( ppage ) ( (ppage)->pghdr.cVersion++ )
#if 0
#define PMDecVersion( ppage ) \
{ \
Assert( (ppage)->pghdr.cVersion > 0 ); \
(ppage)->pghdr.cVersion--; \
}
#else
#define PMDecVersion( ppage ) \
{ \
if ( (ppage)->pghdr.cVersion > 0 ) \
--(ppage)->pghdr.cVersion; \
}
#endif
#define SetPgno( ppage, pgno ) \
ThreeBytesFromL( (ppage)->pgnoThisPage, (pgno) )
#define SetPgnoNext( ppage, pgno ) \
ThreeBytesFromL( (ppage)->pghdr.pgnoNext, (pgno) )
#define SetPgnoPrev( ppage, pgno ) \
ThreeBytesFromL( (ppage)->pghdr.pgnoPrev, (pgno) )
#define PgnoFromPage( ppage, ppgno ) \
LFromThreeBytes( *(ppgno), (ppage)->pgnoThisPage )
#ifdef DEBUG
#define PgnoNextFromPage( pssib, ppgno ) \
{ CheckSSIB( pssib ); LFromThreeBytes( *(ppgno), (pssib)->pbf->ppage->pghdr.pgnoNext ); }
#define PgnoPrevFromPage( pssib, ppgno ) \
{ CheckSSIB( (pssib) ); LFromThreeBytes( *(ppgno), (pssib)->pbf->ppage->pghdr.pgnoPrev ) }
#else
#define PgnoNextFromPage( pssib, ppgno ) \
LFromThreeBytes( *(ppgno), (pssib)->pbf->ppage->pghdr.pgnoNext )
#define PgnoPrevFromPage( pssib, ppgno ) \
LFromThreeBytes( *(ppgno), (pssib)->pbf->ppage->pghdr.pgnoPrev )
#endif
#define absdiff( x, y ) ( (x) > (y) ? (x)-(y) : (y)-(x) )
#define pgdiscont( pgno1, pgno2 ) \
( ( (pgno1) == 0 ) || ( (pgno2) == 0 ) ? 0 \
: absdiff( (pgno1), (pgno2) ) / cpgDiscont )
#define ibPgnoPrevPage ( (INT) (ULONG_PTR)&((PAGE *)0)->pghdr.pgnoPrev )
#define ibPgnoNextPage ( (INT) (ULONG_PTR)&((PAGE *)0)->pghdr.pgnoNext )
#define ibCbFreeTotal ( (INT) (ULONG_PTR)&((PAGE *)0)->pghdr.cbFreeTotal )
#define ibCtagMac ( (INT) (ULONG_PTR)&((PAGE *)0)->pghdr.ctagMac )
#define ibPgtyp ( (INT) (ULONG_PTR)&((PAGE *)0)->pgtyp )
#define CbLastFreeSpace(ppage) \
((ppage)->pghdr.ibLastUsed \
- sizeof(PGHDR) \
- sizeof(TAG) * (ppage)->pghdr.ctagMac)
#define IbCbFromPtag( ibP, cbP, ptagP ) \
{ TAG *_ptagT = ptagP; \
(ibP) = _ptagT->ib; \
(cbP) = _ptagT->cb; \
}
#define PtagFromIbCb( ptagP, ibP, cbP ) \
{ TAG *_ptagT = ptagP; \
_ptagT->ib = (SHORT)(ibP); \
_ptagT->cb = (SHORT)(cbP); \
}
#ifdef DEBUG
#define PMGet( pssib, itagT ) CallS( ErrPMGet( pssib, itagT ) )
#else
#define PMGet( pssib, itagT ) \
{ \
PAGE *ppageT_ = (pssib)->pbf->ppage; \
TAG *ptagT_ = &(ppageT_->rgtag[itagT]); \
Assert( itagT >= 0 ); \
Assert( itagT < (pssib)->pbf->ppage->pghdr.ctagMac ); \
(pssib)->line.pb = (BYTE *)ppageT_ + ptagT_->ib; \
(pssib)->line.cb = ptagT_->cb; \
}
#endif
#define ItagPMMost( ppage ) ((ppage)->pghdr.ctagMac - 1)
BOOL FPMFreeTag( SSIB *pssib, INT citagReq );
#ifdef DEBUG
#define CbPMFreeSpace( pssib ) ( CheckSSIB(pssib), \
((INT)(pssib)->pbf->ppage->pghdr.cbFreeTotal) )
#else
#define CbPMFreeSpace( pssib ) ( (INT)(pssib)->pbf->ppage->pghdr.cbFreeTotal )
#endif
#define ErrPMCheckFreeSpace( pssib, cbT ) \
( ((INT)(pssib)->pbf->ppage->pghdr.cbFreeTotal) < cbT ? \
errPMOutOfPageSpace : JET_errSuccess )
#define PMAllocFreeSpace( pssib, cb ) \
{ \
Assert( (INT)(pssib)->pbf->ppage->pghdr.cbFreeTotal >= cb ); \
(pssib)->pbf->ppage->pghdr.cbFreeTotal -= cb; \
}
#define PMFreeFreeSpace( pssib, cb ) \
{ \
Assert( (INT)(pssib)->pbf->ppage->pghdr.cbFreeTotal >= 0 ); \
(pssib)->pbf->ppage->pghdr.cbFreeTotal += (SHORT)cb; \
Assert( (INT)(pssib)->pbf->ppage->pghdr.cbFreeTotal < cbPage ); \
}
#ifdef DEBUG
#define AssertBTFOP(pssib) \
Assert( PgtypPMPageTypeOfPage((pssib)->pbf->ppage) == pgtypSort || \
PgtypPMPageTypeOfPage((pssib)->pbf->ppage) == pgtypFDP || \
(pssib)->itag != 0 || \
( CbNDKey( (pssib)->line.pb ) == 0 && \
!FNDBackLink( *(pssib)->line.pb ) ) \
)
#else
#define AssertBTFOP( pssib )
#endif
#define PbPMGetChunk(pssib, ib) &(((BYTE *)((pssib)->pbf->ppage))[ib])
INT CbPMLinkSpace( SSIB *pssib );
TS TsPMTagstatus( PAGE *ppage, INT itag );
VOID PMNewPage( PAGE *ppage, PGNO pgno, PGTYP pgtyp, PGNO pgnoFDP );
INT ItagPMQueryNextItag( SSIB *pssib );
ERR ErrPMInsert( SSIB *pssib, LINE *rgline, INT cline );
VOID PMDelete( SSIB *ssib );
ERR ErrPMReplace( SSIB *pssib, LINE *rgline, INT cline );
ERR ErrPMGet( SSIB *pssib, INT itag );
VOID PMGetLink( SSIB *pssib, INT itag, LINK *plink );
VOID PMExpungeLink( SSIB *pssib );
VOID PMReplaceWithLink( SSIB *pssib, SRID srid );
VOID PMReplaceLink( SSIB *pssib, SRID srid );
INT CPMIFreeTag( PAGE *ppage );
BOOL FPMEmptyPage( SSIB *pssib );
BOOL FPMLastNodeToDelete( SSIB *pssib );
VOID PMDirty( SSIB *pssib );
VOID PMReadAsync( PIB *ppib, PN pn );
ERR ErrPMAccessPage( FUCB *pfucb, PGNO pgno );
#ifdef DEBUG
VOID PageConsistent( PAGE *ppage );
#endif