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TSglQueBase Class Reference

class TSglQueBase

A base class that provides implementation for the singly linked list header.

It also encapsulates the offset value of a link object.

The class is abstract and is not intended to be instantiated.

Public Member Functions
IMPORT_C TBool	IsEmpty ()
IMPORT_C void	Reset ()
IMPORT_C void	SetOffset ( TInt )

Protected Member Functions
	TSglQueBase ()
	TSglQueBase ( TInt )
IMPORT_C void	DoAddFirst ( TAny *)
IMPORT_C void	DoAddLast ( TAny *)
IMPORT_C void	DoRemove ( TAny *)

Private Member Functions
	TSglQueBase (const TSglQueBase &)
TSglQueBase &	operator= (const TSglQueBase &)

Protected Attributes
TSglQueLink *	iHead
TSglQueLink *	iLast
TInt	iOffset

Constructor & Destructor Documentation

TSglQueBase()

IMPORT_C

TSglQueBase

(

)

[protected]

Default constructor.

It sets:

1. iHead to Null.

2. iLast to point to the head of queue.

3. iOffset to zero.

iHead iLast iOffset

TSglQueBase(TInt)

IMPORT_C

TSglQueBase

(

TInt

aOffset

)

[protected]

Constructor with specified offset.

It sets:

1. iHead to Null

2. iLast to point to the head of queue.

3. iOffset to the specified value.

panic: USER 75, if aOffset is not divisible by four

iHead iLast iOffset

Parameters

TInt aOffset

The offset of a link object within an element.

TSglQueBase(const TSglQueBase &)

TSglQueBase

(

const TSglQueBase &

aQue

)

[private]

Parameters

const TSglQueBase & aQue

Member Functions Documentation

DoAddFirst(TAny *)

IMPORT_C void

DoAddFirst

(

TAny *

aPtr

)

[protected]

Implements the insertion of a list element at the front of the singly linked list.

This function is called by TSglQue::AddFirst() .

TSglQue::AddFirst

Parameters

TAny * aPtr

An untyped pointer to the element to be inserted.

DoAddLast(TAny *)

IMPORT_C void

DoAddLast

(

TAny *

aPtr

)

[protected]

Implements the insertion of a list element at the back of the singly linked list.

This function is called by TSglQue::AddLast() .

TSglQue::AddLast

Parameters

TAny * aPtr

An untyped pointer to the element to be inserted.

DoRemove(TAny *)

IMPORT_C void

DoRemove

(

TAny *

aPtr

)

[protected]

Implements the removal of a list element from the singly linked list.

This function is called by TSglQue::Remove() .

TSglQue::Remove

Parameters

TAny * aPtr

An untyped pointer to the element to be removed.

IsEmpty()

IMPORT_C TBool

IsEmpty

(

)

const

Tests whether the singly linked list is empty, i.e. has no list elements.

Reset()

IMPORT_C void

Reset

(

)

Empties the singly linked list.

After a call to this function, there are no elements queued from the header; the elements are orphaned. Special care must be taken when list elements are CBase derived objects, i.e. are allocated on the heap.

SetOffset(TInt)

IMPORT_C void

SetOffset

(

TInt

aOffset

)

Sets the offset of the link object from the start of a singly linked list element.

panic: USER 75, if aOffset is not divisible by four.

TSglQue

Parameters

TInt aOffset

The offset of the link object from the start of a singly linked list element.

operator=(const TSglQueBase &)

TSglQueBase &

operator=

(

const TSglQueBase &

aQue

)

[private]

Parameters

const TSglQueBase & aQue

Member Data Documentation

TSglQueLink * iHead

TSglQueLink *

iHead

[protected]

A pointer to the first element in the list.

TSglQueLink * iLast

TSglQueLink *

iLast

[protected]

A pointer to the last element in the list.

TInt iOffset

TInt

iOffset

[protected]

The offset of a component link object within elements that form the list.