550 lines
16 KiB
C++
550 lines
16 KiB
C++
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//+---------------------------------------------------------------------------
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//
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// Microsoft Windows
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// Copyright (C) Microsoft Corporation, 1991 - 1999
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//
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// File: filidmap.cxx
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//
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// Contents: FileId to wid mapping using hashed access
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//
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// History: 07-May-97 SitaramR Created
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//
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// Notes: Only ntfs 5.0 wids are added to the file id map because all
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// non-ntfs 5.0 wids map to fileIdInvalid, which means that there
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// will be too many collisions on fileIdInvalid, which will degrade
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// the performance of the hashed access. One drawback of mapping
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// only ntfs 5.0 wids is that the count of wids in fileid map and
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// property store cannot be checked for equality to detect
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// corruption as is done for the strings table. However, there is a
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// correlation between a count mismatch in strings table and in
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// file id map table because the file id map table is flushed before
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// the strings table. As a result, when a corruption is detected
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// in strings table, a corruption error is thrown and the processing
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// for that corruption error reinitializes both strings table and the
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// file id map table.
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//
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//----------------------------------------------------------------------------
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#include <pch.cxx>
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#pragma hdrstop
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#include <filidmap.hxx>
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#include <mmstrm.hxx>
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#include <cistore.hxx>
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#include <prpstmgr.hxx>
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#include <propiter.hxx>
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#include <cicat.hxx>
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//+---------------------------------------------------------------------------
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//
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// Member: CFileIdMap::CFileIdMap
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//
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// Synopsis: Constructor
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//
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// Arguments: [propStoreMgr] -- Property store
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// [cicat] -- CiCat
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//
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// History: 07-May-97 SitaramR Created
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//
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//----------------------------------------------------------------------------
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CFileIdMap::CFileIdMap( CPropStoreManager &propStoreMgr )
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: CPersHash( propStoreMgr, FALSE ),
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_cCacheEntries( 0 )
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#if CIDBG == 1
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, _cCacheHits( 0 ),
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_cCacheNegativeHits( 0 ),
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_cCacheMisses( 0 ),
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_cCacheNegativeMisses( 0 )
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#endif
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{
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}
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//+---------------------------------------------------------------------------
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//
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// Member: CFileIdMap::FastInit
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//
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// Synopsis: Fast initialization
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//
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// Arguments: [pStorage] -- Ci storage
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// [pwcsCatDir] -- Catalog directory
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// [pwcsFile] -- File id file name
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// [version] -- Content index version
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//
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// History: 28-Jul-97 SitaramR Created
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// 13-Mar-98 KitmanH Passed in True to
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// CPerHash::FastInit to specify
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// that a FileIdMap is wanted
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//
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//----------------------------------------------------------------------------
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BOOL CFileIdMap::FastInit( CiStorage * pStorage,
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ULONG version )
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{
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return CPersHash::FastInit(pStorage, version, TRUE);
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}
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//+---------------------------------------------------------------------------
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//
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// Member: CFileIdMap::LongInit
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//
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// Synopsis: Initialization that may take a long time
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//
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// Arguments: [version] -- CI version
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// [fDirtyShutdown] -- Set to TRUE if the previous shutdown
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// was dirty.
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//
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// History: 28-Jul-97 SitaramR Created
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//
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//----------------------------------------------------------------------------
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void CFileIdMap::LongInit ( ULONG version, BOOL fDirtyShutdown )
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{
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CPersHash::LongInit( version, fDirtyShutdown );
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}
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//+---------------------------------------------------------------------------
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//
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// Member: CFileIdMap::LokFlush
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//
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// Synopsis: Flushes fileid map
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//
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// History: 28-Jul-97 SitaramR Created
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// 27-Feb-98 KitmanH Don't flush if catalog is
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// read-only
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//
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//----------------------------------------------------------------------------
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void CFileIdMap::LokFlush()
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{
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if ( !_fIsReadOnly )
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CPersHash::LokFlush();
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} //LokFlush
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//+-------------------------------------------------------------------------
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//
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// Member: CFileIdMap::AddToCache, private
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//
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// Synopsis: Adds an entry to the cache, or overwrites wid if the
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// entry currently exists. The oldest entry is bumped out.
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// Caching an entry with widInvalid is valid.
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//
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// Arguments: [fileId] -- FileId to add
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// [wid] -- VolumeId to add
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// [volumeId] -- VolumeId to add
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//
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// History: 22-Jul-98 dlee Created
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//
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//--------------------------------------------------------------------------
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void CFileIdMap::AddToCache(
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FILEID & fileId,
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WORKID wid,
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VOLUMEID volumeId )
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{
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// First look for the fileid/volumeid currently in the cache
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for ( unsigned iCache = 0; iCache < _cCacheEntries; iCache++ )
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{
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if ( _aCache[ iCache ].fileId == fileId &&
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_aCache[ iCache ].volumeId == volumeId )
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{
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_aCache[ iCache ].wid = wid;
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return;
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}
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}
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Win4Assert( _cCacheEntries <= cFileIdMapCacheEntries );
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// Bump out the oldest item and put the new item first in the array
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unsigned cToMove;
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if ( _cCacheEntries == cFileIdMapCacheEntries )
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{
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cToMove = cFileIdMapCacheEntries - 1;
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}
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else
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{
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cToMove = _cCacheEntries;
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_cCacheEntries++;
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}
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RtlMoveMemory( & _aCache[ 1 ],
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& _aCache[ 0 ],
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sizeof SFileIdMapEntry * cToMove );
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_aCache[0].fileId = fileId;
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_aCache[0].volumeId = volumeId;
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_aCache[0].wid = wid;
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} //AddToCache
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//+-------------------------------------------------------------------------
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//
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// Member: CFileIdMap::FindInCache, private
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//
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// Synopsis: Locates a workid in the cache given a fileid and volumeid
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//
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// Arguments: [fileId] -- FileId of entry to find
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// [volumeId] -- VolumeId of entry to find
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// [wid] -- Returns the workid if found
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//
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// Returns: TRUE if found or FALSE if not found
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//
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// History: 22-Jul-98 dlee Created
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//
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//--------------------------------------------------------------------------
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BOOL CFileIdMap::FindInCache(
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FILEID & fileId,
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VOLUMEID volumeId,
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WORKID & wid )
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{
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for ( unsigned iCache = 0; iCache < _cCacheEntries; iCache++ )
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{
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if ( _aCache[ iCache ].fileId == fileId &&
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_aCache[ iCache ].volumeId == volumeId )
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{
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wid = _aCache[ iCache ].wid;
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#if CIDBG == 1
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ciDebugOut(( DEB_USN,
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"fim::find cache worked %#I64x %#x, vol %wc\n",
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fileId, wid, volumeId ));
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_cCacheHits++;
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if ( widInvalid == wid )
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_cCacheNegativeHits++;
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#endif
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return TRUE;
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}
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}
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return FALSE;
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} //FindInCache
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//+-------------------------------------------------------------------------
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//
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// Member: CFileIdMap::RemoveFromCache, private
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//
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// Synopsis: Removes the item from the cache if it exists
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//
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// Arguments: [fileId] -- FileId of entry to remove (only used for assert)
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// [wid] -- Workid of entry to remove
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//
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// History: 22-Jul-98 dlee Created
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//
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//--------------------------------------------------------------------------
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void CFileIdMap::RemoveFromCache(
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FILEID & fileId,
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WORKID wid )
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{
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for ( unsigned iCache = 0; iCache < _cCacheEntries; iCache++ )
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{
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if ( _aCache[ iCache ].wid == wid )
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{
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Win4Assert( _aCache[ iCache ].fileId == fileId );
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RtlCopyMemory( & _aCache[ iCache ],
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& _aCache[ iCache + 1 ],
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sizeof SFileIdMapEntry * ( _cCacheEntries - iCache - 1 ) );
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_cCacheEntries--;
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break;
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}
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}
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} //RemoveFromCache
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//+-------------------------------------------------------------------------
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//
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// Member: CFileIdMap::LokFind, private
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//
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// Synopsis: Given fileId, find workid.
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//
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// Arguments: [fileId] - FileId to locate
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// [volumeId] - Volume id of fileid
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//
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// Returns: Workid of FileId
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//
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// History: 07-May-97 SitaramR Created
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//
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// Notes: File ids are not unique across different volumes, hence the
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// need for volume ids.
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//
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//--------------------------------------------------------------------------
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WORKID CFileIdMap::LokFind( FILEID fileId, VOLUMEID volumeId )
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{
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Win4Assert( _fFullInit );
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WORKID wid;
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if ( FindInCache( fileId, volumeId, wid ) )
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return wid;
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#if CIDBG == 1
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_cCacheMisses++;
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#endif
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#ifdef DO_STATS
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unsigned cSearchLen = 0;
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#endif
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CShortWidList list( HashFun(fileId), _hTable );
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for ( wid = list.WorkId(); wid != widInvalid; wid = list.NextWorkId() )
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{
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#ifdef DO_STATS
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cSearchLen++;
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#endif
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XPrimaryRecord rec( _PropStoreMgr, wid );
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PROPVARIANT propVar;
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BOOL fFound = _PropStoreMgr.ReadProperty( rec.GetReference(),
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pidFileIndex,
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propVar );
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ciDebugOut(( DEB_ITRACE, "trying wid %#x, fFound %d, fid %#I64x\n",
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wid, fFound, propVar.uhVal.QuadPart ));
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if ( fFound && propVar.uhVal.QuadPart == fileId )
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{
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Win4Assert( propVar.vt == VT_UI8 );
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BOOL fFound = _PropStoreMgr.ReadProperty( rec.GetReference(),
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pidVolumeId,
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propVar );
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if ( fFound && propVar.ulVal == volumeId )
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{
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Win4Assert( propVar.vt == VT_UI4 );
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#ifdef DO_STATS
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_hTable.UpdateStats( cSearchLen );
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#endif
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ciDebugOut(( DEB_USN, "fim::find worked %#I64x %#x, vol %wc\n",
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fileId, wid, volumeId ));
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AddToCache( fileId, wid, volumeId );
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return wid;
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}
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else
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{
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ciDebugOut(( DEB_USN, "fim::find fileid match, but not volid: %#x, %#x\n",
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propVar.ulVal, volumeId ));
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}
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}
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}
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ciDebugOut(( DEB_USN, "fim::find failed %#I64x, vol %wc\n", fileId, volumeId ));
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#if CIDBG == 1
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_cCacheNegativeMisses++;
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#endif
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//
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// Often, a new file is looked up multiple times before it is added, so
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// add the widInvalid entry to the cache. Negative lookups are slow.
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//
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AddToCache( fileId, widInvalid, volumeId );
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return widInvalid;
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} //LokFind
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//+-------------------------------------------------------------------------
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//
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// Member: CFileIdMap::LokAdd
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//
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// Synopsis: Add a new fileid to wid mapping
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//
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// Arguments: [fileId] -- File Id
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// [wid] -- Workid
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//
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// History: 07-May-97 SitaramR Created
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//
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//--------------------------------------------------------------------------
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void CFileIdMap::LokAdd( FILEID fileId, WORKID wid, VOLUMEID volumeId )
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{
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ciDebugOut(( DEB_USN, "Adding map fileid %#I64x -> wid %x, vol %wc\n",
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fileId, wid, volumeId ));
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Win4Assert( fileIdInvalid != fileId );
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Win4Assert( _fFullInit );
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//
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// Must grow hash table first, as it grovels through property store.
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//
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if ( _hTable.IsFull() )
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GrowHashTable();
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AddToCache( fileId, wid, volumeId );
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_hTable.Add ( HashFun(fileId), wid );
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} //LokAdd
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//+---------------------------------------------------------------------------
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//
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// Member: CFileIdMap::LokDelete
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//
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// Synopsis: Delete file id from table
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//
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// Arguments: [fileId] -- FileId to remove
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// [wid] -- Workid to remove
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//
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// History: 07-May-97 SitaramR Created.
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||
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//
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//----------------------------------------------------------------------------
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|
|
void CFileIdMap::LokDelete( FILEID fileId, WORKID wid )
|
||
|
|
{
|
||
|
|
ciDebugOut(( DEB_USN, "Removing map fileid %#I64x, %#x\n", fileId, wid ));
|
||
|
|
|
||
|
|
RemoveFromCache( fileId, wid );
|
||
|
|
|
||
|
|
_hTable.Remove( HashFun( fileId ), wid, TRUE );
|
||
|
|
} //LokDelete
|
||
|
|
|
||
|
|
//+---------------------------------------------------------------------------
|
||
|
|
//
|
||
|
|
// Member: CFileIdMap::HashAll
|
||
|
|
//
|
||
|
|
// Synopsis: Re-hash all fileId's (after hash table growth)
|
||
|
|
//
|
||
|
|
// History: 07-May-97 May Created
|
||
|
|
//
|
||
|
|
//----------------------------------------------------------------------------
|
||
|
|
|
||
|
|
void CFileIdMap::HashAll()
|
||
|
|
{
|
||
|
|
// Count the number of hash table entries and grow the hash table
|
||
|
|
|
||
|
|
{
|
||
|
|
CPropertyStoreWids iter( _PropStoreMgr );
|
||
|
|
|
||
|
|
unsigned cWids = 0;
|
||
|
|
|
||
|
|
for ( WORKID wid = iter.WorkId(); wid != widInvalid; wid = iter.NextWorkId() )
|
||
|
|
{
|
||
|
|
if ( _fAbort )
|
||
|
|
{
|
||
|
|
ciDebugOut(( DEB_WARN,
|
||
|
|
"Stopping FileIdMap::HashAll because of shutdown\n" ));
|
||
|
|
THROW( CException(STATUS_TOO_LATE) );
|
||
|
|
}
|
||
|
|
|
||
|
|
PROPVARIANT propVar;
|
||
|
|
BOOL fFound = _PropStoreMgr.ReadPrimaryProperty( wid, pidFileIndex, propVar );
|
||
|
|
|
||
|
|
// Only ntfs 5.0 wids have valid fileid's
|
||
|
|
|
||
|
|
if ( fFound &&
|
||
|
|
( VT_UI8 == propVar.vt ) &&
|
||
|
|
( fileIdInvalid != propVar.uhVal.QuadPart ) )
|
||
|
|
cWids++;
|
||
|
|
}
|
||
|
|
|
||
|
|
GrowToSize( cWids );
|
||
|
|
}
|
||
|
|
|
||
|
|
// Add the wids to the hash table
|
||
|
|
|
||
|
|
CPropertyStoreWids iter( _PropStoreMgr );
|
||
|
|
|
||
|
|
for ( WORKID wid = iter.WorkId(); wid != widInvalid; wid = iter.NextWorkId() )
|
||
|
|
{
|
||
|
|
if ( _fAbort )
|
||
|
|
{
|
||
|
|
ciDebugOut(( DEB_WARN,
|
||
|
|
"Stopping FileIdMap::HashAll because of shutdown\n" ));
|
||
|
|
THROW( CException(STATUS_TOO_LATE) );
|
||
|
|
}
|
||
|
|
|
||
|
|
PROPVARIANT propVar;
|
||
|
|
BOOL fFound = _PropStoreMgr.ReadPrimaryProperty( wid, pidFileIndex, propVar );
|
||
|
|
|
||
|
|
//
|
||
|
|
// Only ntfs 5.0 wids have valid fileid's
|
||
|
|
//
|
||
|
|
if ( fFound &&
|
||
|
|
( VT_UI8 == propVar.vt ) &&
|
||
|
|
( fileIdInvalid != propVar.uhVal.QuadPart ) )
|
||
|
|
_hTable.Add ( HashFun( propVar.uhVal.QuadPart ), wid );
|
||
|
|
}
|
||
|
|
|
||
|
|
#if 0
|
||
|
|
|
||
|
|
//
|
||
|
|
// Look-up every file to see what the hashing looks like.
|
||
|
|
//
|
||
|
|
|
||
|
|
{
|
||
|
|
CPropertyStoreWids iter( _PropStoreMgr );
|
||
|
|
|
||
|
|
unsigned cWids = 0;
|
||
|
|
|
||
|
|
for ( WORKID wid = iter.WorkId(); wid != widInvalid; wid = iter.NextWorkId() )
|
||
|
|
{
|
||
|
|
XPrimaryRecord rec( _PropStoreMgr, wid );
|
||
|
|
PROPVARIANT propVar;
|
||
|
|
BOOL fFound = _PropStoreMgr.ReadProperty( rec.GetReference(),
|
||
|
|
pidFileIndex,
|
||
|
|
propVar );
|
||
|
|
|
||
|
|
// Only ntfs 5.0 wids have valid fileid's
|
||
|
|
|
||
|
|
if ( fFound &&
|
||
|
|
( VT_UI8 == propVar.vt ) &&
|
||
|
|
( fileIdInvalid != propVar.uhVal.QuadPart ) )
|
||
|
|
{
|
||
|
|
FILEID fid = propVar.uhVal.QuadPart;
|
||
|
|
_PropStoreMgr.ReadProperty( rec.GetReference(),
|
||
|
|
pidVolumeId,
|
||
|
|
propVar );
|
||
|
|
LokFind( fid, propVar.ulVal );
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
ciDebugOut(( DEB_FORCE,
|
||
|
|
"hash: size %d count %d maxchain %d searches %d length %d\n",
|
||
|
|
_hTable.Size(),
|
||
|
|
_hTable.Count(),
|
||
|
|
_hTable._cMaxChainLen,
|
||
|
|
_hTable._cTotalSearches,
|
||
|
|
_hTable._cTotalLength ));
|
||
|
|
}
|
||
|
|
#endif
|
||
|
|
} //HashAll
|
||
|
|
|
||
|
|
//+-------------------------------------------------------------------------
|
||
|
|
//
|
||
|
|
// Member: CFileIdMap::HashFun
|
||
|
|
//
|
||
|
|
// Synopsis: Hash function for fileid's
|
||
|
|
//
|
||
|
|
// Arguments: [fileId] - FileId to hash
|
||
|
|
//
|
||
|
|
// History: 07-May-97 SitaramR Created
|
||
|
|
//
|
||
|
|
//--------------------------------------------------------------------------
|
||
|
|
|
||
|
|
unsigned CFileIdMap::HashFun( FILEID fileId )
|
||
|
|
{
|
||
|
|
//
|
||
|
|
// The lower 32 bits of the fileid are unique at any given time. The
|
||
|
|
// upper 32 bits of the fileid represent a sequence number that is
|
||
|
|
// incremented every time one of the lower 32 bits number is reused.
|
||
|
|
// So, a good hash function is to simply use the lower 32 bits.
|
||
|
|
//
|
||
|
|
|
||
|
|
return (unsigned) fileId;
|
||
|
|
} //HashFun
|
||
|
|
|
||
|
|
|