SListQueue Class Reference
[Embedded Linked List Package]

Queue head for SListItem elements supporting FIFO operations. More...

#include <list.h>

Collaboration diagram for SListQueue:

[legend]

List of all members.

Public Member Functions
	SListQueue (void)
	Default constructor.
	~SListQueue (void)
	Default destructor -- asserts that queue is empty.
bool	Empty (void) const
	Is queue empty?
void	Reinitialize (void)
	Reinitialize queue head.
void	PrependItem (SListItem &item)
	Insert a single item at the front of the queue.
void	AppendItem (SListItem &item)
	Insert a single item at the back of the queue.
void	SpliceAfter (SListItem &before_first, SListItem &last)
	Insert a sublist at the head of the queue.
void	SpliceBefore (SListItem &before_first, SListItem &last)
	Insert a sublist at the tail of the queue.
void	PrependItemsFrom (SListQueue &source)
	Prepends all elements of a list into this.
void	AppendItemsFrom (SListQueue &source)
	Appends all elements of a list into this.
SListItem *	UnlinkNext (void)
	Unlink and reinitialize successor.
SListItem *	UnlinkNextOnly (void)
	Unlink successor without reinitialization.
void	Push (SListItem &item)
	Alias for PrependItem().
SListItem *	Pop (void)
	Alias for UnlinkNext().
void	Enqueue (SListItem &item)
	Alias for AppendItem().
SListItem *	Dequeue (void)
	Alias for UnlinkNext().

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Detailed Description

Queue head for SListItem elements supporting FIFO operations.

Offers the efficiency tradeoff of having a double-pointer list head, but single-pointer elements. This can be used as a memory- saving alternative to ListItem for cases where the following functionality is not needed:

• Removal of arbitrary elements, ListItem::Unlink().
• Removal of predecessor elements, prev->Unlink().
• Reverse iteration, ListForEachReverse.

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Member Function Documentation

bool Empty

(

void

)

const [inline]

Is queue empty?

Checks whether the queue is an empty circular loop.

Return values:

	true	next points to this and prev points to this
	false	The list is linked with other ListItems.

void Reinitialize

(

void

)

[inline]

Reinitialize queue head.

Reinitializes the SListQueue as a singleton circular list.

Warning:

Use with caution - any elements linked into the queue at the time this method is called will be improperly unlinked, and the list pointers of such will certainly become corrupt.

void PrependItem

(

SListItem &

item

)

[inline]

Insert a single item at the front of the queue.

Links an SListItem to this SListQueue's circular list, such that item becomes the first item on the queue, or the immediate successor of the queue head element.

Parameters:

item

SListItem to be inserted.

Warning:

Blindly overwrites pointers in item. If item is linked to another list, that list will become corrupt.

void AppendItem

(

SListItem &

item

)

[inline]

Insert a single item at the back of the queue.

Links an SListItem to this SListQueue's circular list, such that item becomes the last item on the queue, or the immediate predecessor of the queue head element.

Parameters:

item

SListItem to be inserted.

Warning:

Blindly overwrites pointers in item. If item is linked to another list, that list will become corrupt.

void SpliceAfter	(	SListItem &	before_first,
		SListItem &	last
	)			[inline]

Insert a sublist at the head of the queue.

Unlinks a chain of SListItem structures from whatever list they might be linked onto, and prepends them to the beginning of the queue.

Parameters:

	before_first	SListItem on the source list immediately preceding the starting SListItem of the chain to splice.
	last	Final SListItem on the source list of the chain to splice.

void SpliceBefore	(	SListItem &	before_first,
		SListItem &	last
	)			[inline]

Insert a sublist at the tail of the queue.

Unlinks a chain of SListItem structures from whatever list they might be linked onto, and appends them to the end of the queue.

Parameters:

	before_first	SListItem on the source list immediately preceding the starting SListItem of the chain to splice.
	last	Final SListItem on the source list of the chain to splice.

void PrependItemsFrom

(

SListQueue &

source

)

[inline]

Prepends all elements of a list into this.

Splices all items of source onto the beginning of the subject queue. The parameter source is reinitialized as part of the operation. Upon return, source will be empty.

Parameters:

source

List from which items should be transferred.

void AppendItemsFrom

(

SListQueue &

source

)

[inline]

Appends all elements of a list into this.

Splices all items of source onto the end of the subject queue. The parameter source is reinitialized as part of this operation. Upon return, source will be empty.

Parameters:

source

List from which items should be transferred.

SListItem* UnlinkNext

(

void

)

[inline]

Unlink and reinitialize successor.

Unlinks and reinitializes the successor of this entry in the list.

Returns:

Pointer to former successor, or NULL if empty.

SListItem* UnlinkNextOnly

(

void

)

[inline]

Unlink successor without reinitialization.

Unlinks the successor of this entry in the list. Marginally more efficient than UnlinkNext().

Returns:

Pointer to former successor, or NULL if empty.

Warning:

The former successor will have a dangling next pointer.

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The documentation for this class was generated from the following file:

• include/libhfp/list.h

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