Class RFilePagePool

class RFilePagePool : public TCachePagePool;

Description

Uses a file directly to implement the page pool interface MPagePool.

The pages are written sequentially through the file. You should call RFilePagePool::Close() to release the file resource after CreateL(), OpenL(), ReplaceL() or RFilePagePool::Temp(RFs &,const TDesC &,TFileName &,TUint).

A file page pool uses a cache to store pages in-memory and to cache frequently accessed pages. You should provide a cache object (CPageCache) to the pool for this purpose.

Derivation

• MPagePool - Interface to a page pool, the storage abstraction used by the B-trees API.

• TCachePagePool - Provides a page pool with cached pages.

• RFilePagePool - Uses a file directly to implement the page pool interface MPagePool.

Members

Defined in RFilePagePool:

• Attach(RFile &)Sets an existing file to be used for the page pool.
• Close()Flushes cached pages to the file, and closes the file.
• Create(RFs &,const TDesC &,TUint)Creates a new file for the page pool.
• Detach()Ends the use of the file for the page pool, but does not close the file.
• ExtendL(const TAny *,TPageReclamation)
• File()const
• Flush()Flushes the page cache and the file.
• FlushL()Flushes the page cache and the file, leaving with a system-wide error code if an...
• Open(RFs &,const TDesC &,TUint)Opens a file to use for the page pool.
• RFilePagePool()Default constructor.
• RFilePagePool(CPageCache &)Constructor with a page cache for the pool.
• ReadL(TPageRef,TAny *)
• Release()Closes the file without flushing the cache.
• Replace(RFs &,const TDesC &,TUint)Creates or opens a file for the page pool.
• Temp(RFs &,const TDesC &,TFileName &,TUint)Creates and opens a file for the page pool with a unique name.
• WriteL(TPageRef,const TAny *,TPageChange)

Inherited from MPagePool:

• Delete(TPageRef)Deletes a page, ignoring any errors.
• DeleteL(TPageRef)Deletes a page, leaving if an error occurs.
• Pop()Do a pop from the cleanup stack.
• PushL()Pushes this object onto the cleanup stack.

Inherited from TCachePagePool:

• AcquireL()Returns a function that abandons all locked pages for this page pool.
• AllocL()Allocates an unassigned page.
• AssignL(const TAny *,TPageReclamation)Assigns a reference to a new page and unlocks it.
• DoDeleteL(TPageRef)
• LockL(TPageRef)Locks a page and returns a pointer to it.
• Purge()Purge all pages in this pool from the cache.
• Set(CPageCache &)Sets the page cache for the pool.
• TCachePagePool(CPageCache &)
• Unlock(const TAny *,TPageChange)Unlocks a page.
• UpdateL(const TAny *)Updates a page.

IMPORT_C RFilePagePool();

Description

Default constructor.

IMPORT_C RFilePagePool(CPageCache &aCache);

Description

Constructor with a page cache for the pool.

Parameters

inline TInt Open(RFs &aFs, const TDesC &aName, TUint aFileMode);

Description

Opens a file to use for the page pool.

Parameters

Return value

inline TInt Create(RFs &aFs, const TDesC &aName, TUint aFileMode);

Description

Creates a new file for the page pool.

Parameters

Return value

inline TInt Replace(RFs &aFs, const TDesC &aName, TUint aFileMode);

Description

Creates or opens a file for the page pool.

If there is an existing file with the same name, this function overwrites it. If the file does not already exist, it is created.

Parameters

Return value

inline TInt Temp(RFs &aFs, const TDesC &aPath, TFileName &aName, TUint aFileMode);

Description

Creates and opens a file for the page pool with a unique name.

Parameters

Return value

inline void Attach(RFile &aFile);

Description

Sets an existing file to be used for the page pool.

Parameters

IMPORT_C void Close();

Description

Flushes cached pages to the file, and closes the file.

IMPORT_C void Release();

Description

Closes the file without flushing the cache.

IMPORT_C TInt Flush();

Description

Flushes the page cache and the file.

Return value

IMPORT_C void FlushL();

Description

Flushes the page cache and the file, leaving with a system-wide error code if an error occurs.

inline void Detach();

Description

Ends the use of the file for the page pool, but does not close the file.

inline RFile& File() const;

Description

Return value

protected: IMPORT_C virtual TPageRef ExtendL(const TAny *aPage, TPageReclamation aReclamation);

Description

Parameters

Return value

protected: IMPORT_C virtual void WriteL(TPageRef aRef, const TAny *aPage, TPageChange aChange);

Description

Parameters

protected: IMPORT_C virtual void ReadL(TPageRef aRef, TAny *aPage);

Description

Parameters