CFileStore Class Reference

#include <s32file.h>

class CFileStore : public CPersistentStore

Inherits from

CFileStore
- CPersistentStore
  - CStreamStore

Protected Member Type Definitions
typedef	CFileStore ( TNewFunction

Public Member Functions
	~CFileStore()
void	Detach()
RFile &	File()
IMPORT_C CFileStore *	FromL(RFile &)
IMPORT_C CFileStore *	FromL(RFile &, const TFileStoreFactoryFunction)
IMPORT_C CFileStore *	FromLC(RFile &)
IMPORT_C CFileStore *	FromLC(RFile &, const TFileStoreFactoryFunction)
pure virtual TUid	Layout()
IMPORT_C void	MarshalL()
IMPORT_C CFileStore *	OpenL(RFs &, const TDesC &, TUint)
IMPORT_C CFileStore *	OpenL(RFs &, const TDesC &, TUint, const TFileStoreFactoryFunction)
IMPORT_C CFileStore *	OpenLC(RFs &, const TDesC &, TUint)
IMPORT_C CFileStore *	OpenLC(RFs &, const TDesC &, TUint, const TFileStoreFactoryFunction)
void	Reattach(RFile &)
void	Reset()
void	Reset(TInt)
IMPORT_C void	SetTypeL(const TUidType &)
const TUidType &	Type()

Protected Member Functions
	CFileStore(RFile &)
	CFileStore(RFileBuf &, const TUidType &)
IMPORT_C void	ChangedL()
IMPORT_C CFileStore *	CreateL(RFs &, const TDesC &, TUint, TNewFunction)
IMPORT_C CFileStore *	CreateLC(RFs &, const TDesC &, TUint, TNewFunction)
IMPORT_C void	Destruct()
virtual IMPORT_C void	DoCommitL()
virtual IMPORT_C void	DoRevertL()
IMPORT_C CFileStore *	FromL(RFile &, TFileStoreFactoryFunction)
IMPORT_C CFileStore *	FromLC(RFile &, TFileStoreFactoryFunction)
TStreamExchange &	Host()
TBool	IsHost(const MStreamBuf *)
IMPORT_C CFileStore *	NewL(RFile &, TNewFunction)
IMPORT_C CFileStore *	NewLC(RFile &, TNewFunction)
IMPORT_C CFileStore *	OpenL(RFs &, const TDesC &, TUint, TFileStoreFactoryFunction)
IMPORT_C CFileStore *	OpenLC(RFs &, const TDesC &, TUint, TFileStoreFactoryFunction)
IMPORT_C void	RefreshL()
IMPORT_C CFileStore *	ReplaceL(RFs &, const TDesC &, TUint, TNewFunction)
IMPORT_C CFileStore *	ReplaceLC(RFs &, const TDesC &, TUint, TNewFunction)
void	SetSizeL(TInt)
IMPORT_C void	SynchL()
IMPORT_C CFileStore *	TempL(RFs &, const TDesC &, TFileName &, TUint, TNewFunction)
IMPORT_C CFileStore *	TempLC(RFs &, const TDesC &, TFileName &, TUint, TNewFunction)

Inherited Attributes
	CPersistentStore::iRoot

Inherited Functions
	CBase::CBase()
	CBase::Delete(CBase *)
	CBase::Extension_(TUint,TAny &,TAny )
	CBase::operator new(TUint)
	CBase::operator new(TUint,TAny *)
	CBase::operator new(TUint,TLeave)
	CBase::operator new(TUint,TLeave,TUint)
	CBase::operator new(TUint,TUint)
	CBase::~CBase()
	CPersistentStore::CPersistentStore()
	CPersistentStore::Root()const
	CPersistentStore::SetRootL(TStreamId)
	CStreamStore::Commit()
	CStreamStore::CommitL()
	CStreamStore::CompactL()
	CStreamStore::Delete(TStreamId)
	CStreamStore::DeleteL(TStreamId)
	CStreamStore::ExtendL()
	CStreamStore::ReclaimL()
	CStreamStore::Revert()
	CStreamStore::RevertL()

Detailed Description

File based persistent store abstract base class.

The class encapsulates the basic behaviour of file based stores. File based stores are persistent stores, i.e. they have the ability to keep the external representation of objects for longer than the lifetime of the applications which created those objects.

The class forms the base for the direct file store, CDirectFileStore, and the permanent file store, CPermanentFileStore. In general, it is sufficient for pointers to file based store objects to be of type CFileStore, rather than of the concrete file store type.

Existing file stores can be opened using the member functions OpenL(), OpenLC(), FromL() and FromLC(). New file stores, however, must be created using the appropriate member function of the concrete type.

Member Type Definition Documentation

Typedef TNewFunction

typedef CFileStore *(*

TNewFunction

[protected]

Constructor & Destructor Documentation

CFileStore ( RFile & )

IMPORT_C

CFileStore

(

RFile &

aFile

)

[protected]

CFileStore ( RFileBuf &, const TUidType & )

IMPORT_C	CFileStore	(	RFileBuf &	aBuf,
			const TUidType &	aType
		)	[protected]

~CFileStore ( )

IMPORT_C

~CFileStore

(

)

Frees resources owned by the object, prior to its destruction. In particular, it closes the associated file.

Member Function Documentation

ChangedL ( )

IMPORT_C void

ChangedL

(

)

[protected]

CreateL ( RFs &, const TDesC &, TUint, TNewFunction )

IMPORT_C CFileStore *	CreateL	(	RFs &	aFs,
			const TDesC &	aName,
			TUint	aFileMode,
			TNewFunction	aFunction
		)	[protected, static]

CreateLC ( RFs &, const TDesC &, TUint, TNewFunction )

IMPORT_C CFileStore *	CreateLC	(	RFs &	aFs,
			const TDesC &	aName,
			TUint	aFileMode,
			TNewFunction	aFunction
		)	[protected, static]

Destruct ( )

IMPORT_C void

Destruct

(

)

[protected]

Detach ( )

void

Detach

(

)

[inline]

Detaches the file store from its associated file.

In effect, the file store gives up ownership of the file.

Detaching is useful in cases where a file needs to be closed and later re-opened; for example, to give up a write lock for backup purposes.

It is very important that the contents of the file should not change while it is detached.

DoCommitL ( )

IMPORT_C void

DoCommitL

(

)

[protected, virtual]

Reimplemented from CStreamStore::DoCommitL()

Commits any changes to the store. For a store that provides atomic updates, this writes all of the pending updates to the to the permanent storage medium. After committing the store contains all or none of the updates since the last commit/revert.

This function provides the implementation for the public CommitL() function.

DoRevertL ( )

IMPORT_C void

DoRevertL

(

)

[protected, virtual]

Reimplemented from CStreamStore::DoRevertL()

Discards any pending changes to the store. This includes all changes which have not been committed to a permanent storage medium.

This function provides the implementation for the public Revert() function.

Note:

The function need only be implemented by stores that provide atomic updates, as revert has no meaning for other implementations.

File ( )

RFile &

File

(

)

const [inline]

Gets a reference to the file associated with this file store.

This function is called prior to detaching the file store.

FromL ( RFile & )

IMPORT_C CFileStore *

FromL

(

RFile &

aFile

)

[static]

Constructs a file store object from an opened file.

The file must already be open before calling this function.

The resulting file store object is of concrete type, i.e. either CDirectFileStore or CPermanentFileStore. The specific type is determined from the layout information held in the file store.

Note that ownership of the file passes to the store. The referenced RFile is cleared and is no longer valid:

Parameter	Description
aFile	A reference to the opened file.

FromL ( RFile &, const TFileStoreFactoryFunction )

IMPORT_C CFileStore *	FromL	(	RFile &	aFile,
			const TFileStoreFactoryFunction	aFactory
		)	[static]

FromL ( RFile &, TFileStoreFactoryFunction )

IMPORT_C CFileStore *	FromL	(	RFile &	aFile,
			TFileStoreFactoryFunction	aFunction
		)	[protected, static]

FromLC ( RFile & )

IMPORT_C CFileStore *

FromLC

(

RFile &

aFile

)

[static]

Constructs a file store object from an opened file, and places the pointer onto the cleanup stack.

The file must already be open before calling this function.

The resulting file store object is of concrete type, i.e. either CDirectFileStore or CPermanentFileStore. The specific type is determined from the layout information held in the file store.

Note that ownership of the file passes to the store. The referenced RFile is cleared and is no longer valid:

Parameter	Description
aFile	A reference to the opened file.

FromLC ( RFile &, const TFileStoreFactoryFunction )

IMPORT_C CFileStore *	FromLC	(	RFile &	aFile,
			const TFileStoreFactoryFunction	aFactory
		)	[static]

FromLC ( RFile &, TFileStoreFactoryFunction )

IMPORT_C CFileStore *	FromLC	(	RFile &	aFile,
			TFileStoreFactoryFunction	aFunction
		)	[protected, static]

Host ( )

TStreamExchange &

Host

(

)

const [protected, inline]

IsHost ( const MStreamBuf * )

TBool

IsHost

(

const MStreamBuf *

aBuf

)

const [protected, inline]

Layout ( )

TUid

Layout

(

)

const [pure virtual]

Gets the UID that uniquely identifies the specific type of this file store.

This function must be defined and implemented by classes derived from CFileStore. The direct file store, CDirectFileStore and the permanent file store, CPermanentFileStore both implement suitable functions.

Returns: The UID that uniquely identifies the specific type of file store.

MarshalL ( )

IMPORT_C void

MarshalL

(

)

NewL ( RFile &, TNewFunction )

IMPORT_C CFileStore *	NewL	(	RFile &	aFile,
			TNewFunction	aFunction
		)	[protected, static]

NewLC ( RFile &, TNewFunction )

IMPORT_C CFileStore *	NewLC	(	RFile &	aFile,
			TNewFunction	aFunction
		)	[protected, static]

OpenL ( RFs &, const TDesC &, TUint )

IMPORT_C CFileStore *	OpenL	(	RFs &	aFs,
			const TDesC &	aName,
			TUint	aFileMode
		)	[static]

Opens a file containing a store and constructs an appropriate file store object.

The resulting file store object is of concrete type, i.e. either CDirectFileStore or CPermanentFileStore. The specific type is determined from the layout information held in the file store.

Parameter	Description
aFs	Handle to a file server session.
aName	The full path name of the file containing the store.
aFileMode	The mode in which the file is to be accessed. The mode is defined by the TFileMode type.

Returns: A pointer to the new file store object.

OpenL ( RFs &, const TDesC &, TUint, const TFileStoreFactoryFunction )

IMPORT_C CFileStore *	OpenL	(	RFs &	aFs,
			const TDesC &	aName,
			TUint	aFileMode,
			const TFileStoreFactoryFunction	aFactory
		)	[static]

OpenL ( RFs &, const TDesC &, TUint, TFileStoreFactoryFunction )

IMPORT_C CFileStore *	OpenL	(	RFs &	aFs,
			const TDesC &	aName,
			TUint	aFileMode,
			TFileStoreFactoryFunction	aFunction
		)	[protected, static]

OpenLC ( RFs &, const TDesC &, TUint )

IMPORT_C CFileStore *	OpenLC	(	RFs &	aFs,
			const TDesC &	aName,
			TUint	aFileMode
		)	[static]

Opens a file containing a store, constructs an appropriate file store object and places the pointer onto the cleanup stack.

The resulting file store object is of concrete type, i.e. either CDirectFileStore or CPermanentFileStore. The specific type is determined from the layout information held in the file store.

Parameter	Description
aFs	Handle to a file server session.
aName	The full path name of the file containing the store.
aFileMode	The mode in which the file is to be accessed. The mode is defined by the TFileMode type.

Returns: A pointer to the new file store object.

OpenLC ( RFs &, const TDesC &, TUint, const TFileStoreFactoryFunction )

IMPORT_C CFileStore *	OpenLC	(	RFs &	aFs,
			const TDesC &	aName,
			TUint	aFileMode,
			const TFileStoreFactoryFunction	aFactory
		)	[static]

OpenLC ( RFs &, const TDesC &, TUint, TFileStoreFactoryFunction )

IMPORT_C CFileStore *	OpenLC	(	RFs &	aFs,
			const TDesC &	aName,
			TUint	aFileMode,
			TFileStoreFactoryFunction	aFunction
		)	[protected, static]

Reattach ( RFile & )

void

Reattach

(

RFile &

aFile

)

[inline]

Reattaches a file to the file store. The file should be the one that was detached using the Detach() function.

Parameter	Description
aFile	The file to be associated with this file store.

RefreshL ( )

IMPORT_C void

RefreshL

(

)

[protected]

ReplaceL ( RFs &, const TDesC &, TUint, TNewFunction )

IMPORT_C CFileStore *	ReplaceL	(	RFs &	aFs,
			const TDesC &	aName,
			TUint	aFileMode,
			TNewFunction	aFunction
		)	[protected, static]

ReplaceLC ( RFs &, const TDesC &, TUint, TNewFunction )

IMPORT_C CFileStore *	ReplaceLC	(	RFs &	aFs,
			const TDesC &	aName,
			TUint	aFileMode,
			TNewFunction	aFunction
		)	[protected, static]

Reset ( )

void

Reset

(

)

[inline]

Frees the file store s buffer space.

The buffer space is automatically re-allocated when needed.

This function should only be used immediately after a successful call to CommitL() or RevertL().

Reset ( TInt )

void

Reset

(

TInt

aSize

)

[inline]

Frees the file store s buffer space and changes the size of future buffer space allocations.

The buffer space is automatically re-allocated when needed, using the new size value.

This function should only be used immediately after a successful call to CommitL() or RevertL().

Parameter	Description
aSize	The size of future buffer space allocations.

SetSizeL ( TInt )

void

SetSizeL

(

TInt

aSize

)

[protected, inline]

SetTypeL ( const TUidType & )

IMPORT_C void

SetTypeL

(

const TUidType &

aType

)

Sets the UID type of the file store.

The first UID, i.e. the first TUid component, of the TUidType must be the file store type as returned by CFileStore::Layout(), otherwise the function raises a STORE-File 9 panic.

SynchL ( )

IMPORT_C void

SynchL

(

)

[protected]

TempL ( RFs &, const TDesC &, TFileName &, TUint, TNewFunction )

IMPORT_C CFileStore *	TempL	(	RFs &	aFs,
			const TDesC &	aPath,
			TFileName &	aName,
			TUint	aFileMode,
			TNewFunction	aFunction
		)	[protected, static]

TempLC ( RFs &, const TDesC &, TFileName &, TUint, TNewFunction )

IMPORT_C CFileStore *	TempLC	(	RFs &	aFs,
			const TDesC &	aPath,
			TFileName &	aName,
			TUint	aFileMode,
			TNewFunction	aFunction
		)	[protected, static]

Type ( )

const TUidType &

Type

(

)

const [inline]

Gets the UID type of the file store.