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TChunkCreateInfo Struct Reference

struct TChunkCreateInfo

This structure specifies the type and properties of the chunk to be created. It is passed as a parameter to the RChunk::Create() method.

Public Member Functions
	TChunkCreateInfo()
IMPORT_C void	SetCache(TInt)
IMPORT_C void	SetClearByte(TUint8)
IMPORT_C void	SetCode(TInt, TInt)
IMPORT_C void	SetDisconnected(TInt, TInt, TInt)
IMPORT_C void	SetDoubleEnded(TInt, TInt, TInt)
IMPORT_C void	SetGlobal(const TDesC &)
IMPORT_C void	SetNormal(TInt, TInt)
IMPORT_C void	SetOwner(TOwnerType)
IMPORT_C void	SetPaging(const TChunkPagingAtt)
IMPORT_C void	SetReadOnly()
void	SetThreadHeap(TInt, TInt, const TDesC &)

Public Member Enumerations
enum	TChunkCreateVersions { EVersion0, ESupportedVersions }
enum	TChunkPagingAtt { EUnspecified, EPaged, EUnpaged }

Protected Attributes
TUint	iAttributes
TUint8	iClearByte
TBool	iGlobal
TInt	iInitialBottom
TInt	iInitialTop
TInt	iMaxSize
const TDesC *	iName
TOwnerType	iOwnerType
TUint8	iSpare1
TUint	iSpare2
TUint	iType
TUint	iVersionNumber

Constructor & Destructor Documentation

TChunkCreateInfo()

IMPORT_C

TChunkCreateInfo

(

)

Default constructor.

This defaults the chunk to be created to be local, to have no attributes set and to use the default clear byte.

A local chunk is private to the process creating it and is not intended for access by other user processes.

Member Functions Documentation

SetCache(TInt)

IMPORT_C void

SetCache

(

TInt

aMaxSize

)

For use by file server only.

Parameters

TInt aMaxSize

SetClearByte(TUint8)

IMPORT_C void

SetClearByte

(

TUint8

aClearByte

)

Sets the byte value that all memory committed to the chunk will be cleared to.

Parameters

TUint8 aClearByte

SetCode(TInt, TInt)

IMPORT_C void	SetCode	(	TInt	aInitialSize,
			TInt	aMaxSize
		)

Sets the chunk to be created to be user writable and to be marked by the kernel as containing code. This can only be set on local chunks.

RChunk::CreateLocalCode()

Parameters

TInt aInitialSize	The number of bytes committed to this chunk.
TInt aMaxSize	The maximum size to which the reserved region of this chunk can grow.

SetDisconnected(TInt, TInt, TInt)

IMPORT_C void	SetDisconnected	(	TInt	aInitialBottom,
			TInt	aInitialTop,
			TInt	aMaxSize
		)

Set the chunk to be created to have a committed region consisting of an arbitrary set of MMU pages within the reserved region.

RChunk::CreateDisconnectedLocal()

Parameters

TInt aInitialBottom	The offset of the bottom of the new committed region from the base of the chunk's reserved region.
TInt aInitialTop	The offset of the top of the new committed region from the base of the chunk's reserved region.
TInt aMaxSize	The maximum size to which the reserved region of this chunk can grow.

SetDoubleEnded(TInt, TInt, TInt)

IMPORT_C void	SetDoubleEnded	(	TInt	aInitialBottom,
			TInt	aInitialTop,
			TInt	aMaxSize
		)

Sets the chunk to be created to have a commited region that that can be any contiguous subset of the reserved region.

RChunk::CreateDoubleEndedLocal()

Parameters

TInt aInitialBottom	The offset of the bottom of the new committed region from the base of the chunk's reserved region.
TInt aInitialTop	The offset of the top of the new committed region from the base of the chunk's reserved region.
TInt aMaxSize	The maximum size to which the reserved region of this chunk can grow.

SetGlobal(const TDesC &)

IMPORT_C void

SetGlobal

(

const TDesC &

aName

)

Sets the chunk to be created to be global, i.e. it is potentially visible to all processes and is intended for access by other user processes.

Parameters

const TDesC & aName

A reference to a descriptor containing the name to be assigned to the global chunk. The length of the descriptor must be no greater than that allowed for a TKName type.

SetNormal(TInt, TInt)

IMPORT_C void	SetNormal	(	TInt	aInitialSize,
			TInt	aMaxSize
		)

Sets the chunk to be created to have a committed region that always starts at the bottom of the reserved region.

RChunk::CreateLocal()

Parameters

TInt aInitialSize
TInt aMaxSize	The maximum size to which the reserved region of this chunk can grow.

SetOwner(TOwnerType)

IMPORT_C void

SetOwner

(

TOwnerType

aType

)

Sets the owner of the chunk to be created.

Parameters

TOwnerType aType

The owner of the chunk to be created.

SetPaging(const TChunkPagingAtt)

IMPORT_C void

SetPaging

(

const TChunkPagingAtt

aPaging

)

Sets the data paging attributes for the chunk to be created. Any previous calls to this method will be overridden for this TChunkCreateInfo object.

Parameters

const TChunkPagingAtt aPaging

The data paging attributes of the chunk to be created.

SetReadOnly()

IMPORT_C void

SetReadOnly

(

)

Sets the global chunk to be created to be read only. Only the creating process will be able to write to it, not other processes.

Read-Only chunks are currently only available on the Flexible Memory Model.

Chunk must be global.

SetThreadHeap(TInt, TInt, const TDesC &)

void	SetThreadHeap	(	TInt	aInitialSize,
			TInt	aMaxSize,
			const TDesC &	aName
		)

Sets the chunk to be created to be a thread heap chunk. For internal use only.

Parameters

TInt aInitialSize	The number of bytes committed to this chunk.
TInt aMaxSize	The maximum size to which the reserved region of this chunk can grow.
const TDesC & aName	The name to be given to the chunk to be created

Member Enumerations Documentation

Enum TChunkCreateVersions

Currently supported version numbers

Enumerators

EVersion0
ESupportedVersions

Enum TChunkPagingAtt

Attributes that specify whether the chunk to be created is data paged or not.

Enumerators

EUnspecified	The chunk will use the creating process's paging attributes.
EPaged	The chunk will be data paged.
EUnpaged	The chunk will not be data paged.

Member Data Documentation

TUint iAttributes

TUint

iAttributes

[protected]

Attributes to the chunk to be created should have. Should be set from one or more the values in TChunkCreate::TChunkCreateAtt.

TUint8 iClearByte

TUint8

iClearByte

[protected]

The byte to clear all the memory committed to the chunk to.

TBool iGlobal

TBool

iGlobal

[protected]

Specify if chunk is global or not.

TInt iInitialBottom

TInt

iInitialBottom

[protected]

The offset of the bottom of the region to commit to the chunk on creation from the base of the chunk's reserved region. This is only used for double ended and disconnected chunks.

TInt iInitialTop

TInt

iInitialTop

[protected]

The offset of the top of the region to commit to the chunk on creation from the base of the chunk's reserved region. This is only used for double ended and disconnected chunks.

TInt iMaxSize

TInt

iMaxSize

[protected]

The maximum size in bytes of the chunk to be created.

const TDesC * iName

const TDesC *

iName

[protected]

A pointer to a descriptor containing the name to be assigned to global chunks. The length of the descriptor must be no greater than that allowed for a TKName type. Must be NULL for local chunks.

TOwnerType iOwnerType

TOwnerType

iOwnerType

[protected]

An enumeration whose enumerators define the ownership of this chunk handle. If not explicitly specified, EOwnerProcess is taken as default.

TUint8 iSpare1

TUint8

iSpare1

[protected]

TUint iSpare2

TUint

iSpare2

[protected]

TUint iType

TUint

iType

[protected]

The type of the chunk to be created.

TUint iVersionNumber

TUint

iVersionNumber

[protected]

The version number of this TChunkCreateInfo.