nvwa::fc_queue< _Tp, _Alloc > Class Template Reference

Class to represent a fixed-capacity queue. More...

#include <fc_queue.h>

Collaboration diagram for nvwa::fc_queue< _Tp, _Alloc >:

[legend]

List of all members.

Public Types
typedef _Tp	value_type
typedef _Alloc	allocator_type
typedef size_t	size_type
typedef value_type *	pointer
typedef const value_type *	const_pointer
typedef value_type &	reference
typedef const value_type &	const_reference
Public Member Functions
	fc_queue (size_type max_size, const allocator_type &alloc=allocator_type())
	Constructor that creates the queue with a maximum size (capacity).
	fc_queue (const fc_queue &rhs)
	Copy-constructor that copies all elements from another queue.
	~fc_queue ()
	Destructor.
fc_queue &	operator= (const fc_queue &rhs)
	Assignment operator that copies all elements from another queue.
bool	empty () const noexcept
	Checks whether the queue is empty (containing no elements).
bool	full () const noexcept
	Checks whether the queue is full (containing the maximum allowed elements).
size_type	capacity () const noexcept
	Gets the maximum number of allowed elements in the queue.
size_type	size () const noexcept
	Gets the number of existing elements in the queue.
reference	front ()
	Gets the first element in the queue.
const_reference	front () const
	Gets the first element in the queue.
reference	back ()
	Gets the last element in the queue.
const_reference	back () const
	Gets the last element in the queue.
void	push (const value_type &value)
	Inserts a new element at the end of the queue.
void	pop ()
	Discards the first element in the queue.
bool	contains (const value_type &value) const
	Checks whether the queue contains a specific element.
void	swap (fc_queue &rhs)
	Exchanges the elements of two queues.
allocator_type	get_allocator () const
	Gets the allocator of the queue.
Protected Member Functions
pointer	increment (pointer ptr) const noexcept
pointer	decrement (pointer ptr) const noexcept
void	construct (void *ptr, const _Tp &value)
void	destroy (void *ptr)
Protected Attributes
pointer	_M_head
pointer	_M_tail
pointer	_M_begin
pointer	_M_end
allocator_type	_M_alloc

---

Detailed Description

template<class _Tp, class _Alloc = std::allocator<_Tp>>
class nvwa::fc_queue< _Tp, _Alloc >

Class to represent a fixed-capacity queue.

This class has an interface close to std::queue, but it allows very efficient and lockless one-producer, one-consumer access, as long as the producer does not try to queue an element when the queue is already full.

Parameters:

	_Tp	the type of elements in the queue
	_Alloc	allocator to use for memory management

Precondition:

_Tp shall be CopyConstructible and Destructible, and _Alloc shall meet the allocator requirements (Table 28 in the C++11 spec).

---

Member Typedef Documentation

template<class _Tp , class _Alloc = std::allocator<_Tp>>

typedef _Alloc nvwa::fc_queue< _Tp, _Alloc >::allocator_type

template<class _Tp , class _Alloc = std::allocator<_Tp>>

typedef const value_type* nvwa::fc_queue< _Tp, _Alloc >::const_pointer

template<class _Tp , class _Alloc = std::allocator<_Tp>>

typedef const value_type& nvwa::fc_queue< _Tp, _Alloc >::const_reference

template<class _Tp , class _Alloc = std::allocator<_Tp>>

typedef value_type* nvwa::fc_queue< _Tp, _Alloc >::pointer

template<class _Tp , class _Alloc = std::allocator<_Tp>>

typedef value_type& nvwa::fc_queue< _Tp, _Alloc >::reference

template<class _Tp , class _Alloc = std::allocator<_Tp>>

typedef size_t nvwa::fc_queue< _Tp, _Alloc >::size_type

template<class _Tp , class _Alloc = std::allocator<_Tp>>

typedef _Tp nvwa::fc_queue< _Tp, _Alloc >::value_type

---

Constructor & Destructor Documentation

template<class _Tp , class _Alloc = std::allocator<_Tp>>

nvwa::fc_queue< _Tp, _Alloc >::fc_queue	(	size_type	max_size,
		const allocator_type &	alloc = allocator_type()
	)			[inline, explicit]

Constructor that creates the queue with a maximum size (capacity).

Parameters:

	max_size	the maximum size allowed
	alloc	the allocator to use

Precondition:

max_size shall be not be zero

Postcondition:

Unless memory allocation throws an exception, this queue will be constructed with the specified maximum size, and the following conditions will hold:

• empty()
• ! full()
• capacity() == max_size
• size() == 0
• get_allocator() == alloc

template<class _Tp , class _Alloc >

nvwa::fc_queue< _Tp, _Alloc >::fc_queue

(

const fc_queue< _Tp, _Alloc > &

rhs

)

[inline]

Copy-constructor that copies all elements from another queue.

Parameters:

rhs

the queue to copy

Postcondition:

If copy-construction is successful (no exception is thrown during memory allocation and element copy), this queue will have the same elements as rhs.

template<class _Tp , class _Alloc = std::allocator<_Tp>>

nvwa::fc_queue< _Tp, _Alloc >::~fc_queue

(

)

[inline]

Destructor.

It erases all elements and frees memory.

---

Member Function Documentation

template<class _Tp , class _Alloc = std::allocator<_Tp>>

const_reference nvwa::fc_queue< _Tp, _Alloc >::back

(

)

const [inline]

Gets the last element in the queue.

Returns:

const reference to the last element

template<class _Tp , class _Alloc = std::allocator<_Tp>>

reference nvwa::fc_queue< _Tp, _Alloc >::back

(

)

[inline]

Gets the last element in the queue.

Returns:

reference to the last element

template<class _Tp , class _Alloc = std::allocator<_Tp>>

size_type nvwa::fc_queue< _Tp, _Alloc >::capacity

(

)

const [inline]

Gets the maximum number of allowed elements in the queue.

Returns:

the maximum number of allowed elements in the queue

template<class _Tp , class _Alloc = std::allocator<_Tp>>

void nvwa::fc_queue< _Tp, _Alloc >::construct	(	void *	ptr,
		const _Tp &	value
	)			[inline, protected]

template<class _Tp , class _Alloc = std::allocator<_Tp>>

bool nvwa::fc_queue< _Tp, _Alloc >::contains

(

const value_type &

value

)

const [inline]

Checks whether the queue contains a specific element.

Parameters:

value

the value to be compared

Precondition:

value_type shall be EqualityComparable.

Returns:

true if found; false otherwise

template<class _Tp , class _Alloc = std::allocator<_Tp>>

pointer nvwa::fc_queue< _Tp, _Alloc >::decrement

(

pointer

ptr

)

const [inline, protected]

template<class _Tp , class _Alloc = std::allocator<_Tp>>

void nvwa::fc_queue< _Tp, _Alloc >::destroy

(

void *

ptr

)

[inline, protected]

template<class _Tp , class _Alloc = std::allocator<_Tp>>

bool nvwa::fc_queue< _Tp, _Alloc >::empty

(

)

const [inline]

Checks whether the queue is empty (containing no elements).

Returns:

true if it is empty; false otherwise

template<class _Tp , class _Alloc = std::allocator<_Tp>>

const_reference nvwa::fc_queue< _Tp, _Alloc >::front

(

)

const [inline]

Gets the first element in the queue.

Returns:

const reference to the first element

template<class _Tp , class _Alloc = std::allocator<_Tp>>

reference nvwa::fc_queue< _Tp, _Alloc >::front

(

)

[inline]

Gets the first element in the queue.

Returns:

reference to the first element

template<class _Tp , class _Alloc = std::allocator<_Tp>>

bool nvwa::fc_queue< _Tp, _Alloc >::full

(

)

const [inline]

Checks whether the queue is full (containing the maximum allowed elements).

Returns:

true if it is full; false otherwise

template<class _Tp , class _Alloc = std::allocator<_Tp>>

allocator_type nvwa::fc_queue< _Tp, _Alloc >::get_allocator

(

)

const [inline]

Gets the allocator of the queue.

Returns:

the allocator of the queue

template<class _Tp , class _Alloc = std::allocator<_Tp>>

pointer nvwa::fc_queue< _Tp, _Alloc >::increment

(

pointer

ptr

)

const [inline, protected]

template<class _Tp , class _Alloc = std::allocator<_Tp>>

fc_queue& nvwa::fc_queue< _Tp, _Alloc >::operator=

(

const fc_queue< _Tp, _Alloc > &

rhs

)

[inline]

Assignment operator that copies all elements from another queue.

Parameters:

rhs

the queue to copy

Postcondition:

If assignment is successful (no exception is thrown during memory allocation and element copy), this queue will have the same elements as rhs. Otherwise this queue is unchanged (strong exception safety is guaranteed).

template<class _Tp , class _Alloc = std::allocator<_Tp>>

void nvwa::fc_queue< _Tp, _Alloc >::pop

(

)

[inline]

Discards the first element in the queue.

Precondition:

This queue is not empty.

Postcondition:

One element is discarded at the front, size() is decremented by one, and full() is false.

template<class _Tp , class _Alloc = std::allocator<_Tp>>

void nvwa::fc_queue< _Tp, _Alloc >::push

(

const value_type &

value

)

[inline]

Inserts a new element at the end of the queue.

The first element will be discarded if the queue is full.

Parameters:

value

the value to be inserted

Postcondition:

size() <= capacity() && back() == value, unless an exception is thrown, in which case this queue is unchanged (strong exception safety is guaranteed).

template<class _Tp , class _Alloc = std::allocator<_Tp>>

size_type nvwa::fc_queue< _Tp, _Alloc >::size

(

)

const [inline]

Gets the number of existing elements in the queue.

Returns:

the number of existing elements in the queue

template<class _Tp , class _Alloc = std::allocator<_Tp>>

void nvwa::fc_queue< _Tp, _Alloc >::swap

(

fc_queue< _Tp, _Alloc > &

rhs

)

[inline]

Exchanges the elements of two queues.

Parameters:

rhs

the queue to exchange with

Postcondition:

If swapping the allocators does not throw, *this will be swapped with rhs. If swapping the allocators throws with strong exception safety guarantee, this function will also provide such guarantee.

---

Member Data Documentation

template<class _Tp , class _Alloc = std::allocator<_Tp>>

allocator_type nvwa::fc_queue< _Tp, _Alloc >::_M_alloc [protected]

template<class _Tp , class _Alloc = std::allocator<_Tp>>

pointer nvwa::fc_queue< _Tp, _Alloc >::_M_begin [protected]

template<class _Tp , class _Alloc = std::allocator<_Tp>>

pointer nvwa::fc_queue< _Tp, _Alloc >::_M_end [protected]

template<class _Tp , class _Alloc = std::allocator<_Tp>>

pointer nvwa::fc_queue< _Tp, _Alloc >::_M_head [protected]

template<class _Tp , class _Alloc = std::allocator<_Tp>>

pointer nvwa::fc_queue< _Tp, _Alloc >::_M_tail [protected]

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

• fc_queue.h