A queue with a limited size and the ability to query only specific values. More...

#include <ConditionalQueue.h>

Public Member Functions
	ConditionalQueue (size_t max_size)

	~ConditionalQueue ()=default

void	Push (T &&value, std::unique_lock< std::mutex > &lock)
	Place a new object at the end of the queue.

template<typename... Args>
void	Emplace (std::unique_lock< std::mutex > &lock, Args &&... args)
	Same as Push(), but constructs in place.

template<typename Condition >
bool	PopIf (T &result, std::unique_lock< std::mutex > &lock, Condition condition)
	Pop an object from the queue for which a specified condition holds.

void	NotifyOneChange ()
	Notify the queue that the condition for values might have changed.

void	Finish (std::unique_lock< std::mutex > &lock)
	Makes PopIf return false once the queue is empty.

size_t	Size (std::unique_lock< std::mutex > &lock) const

size_t	MaxSize () const

Private Member Functions
template<typename Condition >
std::list< T >::iterator	GetNext (Condition &condition)

Private Attributes
std::list< T >	values_

bool	is_finished_

size_t	max_size_

std::condition_variable	pop_condition_

std::condition_variable	push_condition_

Detailed Description

template<typename T>
class casacore::sisco::ConditionalQueue< T >

A queue with a limited size and the ability to query only specific values.

The queue is synchronized, but the caller needs to maintain a mutex.

The reason for this is that if the condition requires locking, the same lock can be used for the queue operations and the condition.

Definition at line 20 of file ConditionalQueue.h.

Constructor & Destructor Documentation

◆ ConditionalQueue()

template<typename T >

casacore::sisco::ConditionalQueue< T >::ConditionalQueue ( size_t max_size )

inline

Definition at line 22 of file ConditionalQueue.h.

◆ ~ConditionalQueue()

template<typename T >

casacore::sisco::ConditionalQueue< T >::~ConditionalQueue ( )

default

Member Function Documentation

◆ Emplace()

template<typename T >

template<typename... Args>

void casacore::sisco::ConditionalQueue< T >::Emplace	(	std::unique_lock< std::mutex > &	lock,
		Args &&...	args
	)

inline

Same as Push(), but constructs in place.

We need to notify all, because if only one thread is awoken that is looking for a specific condition that is not met, the signal is lost while another nother thread's condition may be met.

Definition at line 50 of file ConditionalQueue.h.

References casacore::sisco::ConditionalQueue< T >::max_size_, casacore::sisco::ConditionalQueue< T >::pop_condition_, casacore::sisco::ConditionalQueue< T >::push_condition_, and casacore::sisco::ConditionalQueue< T >::values_.

◆ Finish()

template<typename T >

void casacore::sisco::ConditionalQueue< T >::Finish ( std::unique_lock< std::mutex > & lock )

inline

Makes PopIf return false once the queue is empty.

Definition at line 104 of file ConditionalQueue.h.

References casacore::sisco::ConditionalQueue< T >::is_finished_, and casacore::sisco::ConditionalQueue< T >::push_condition_.

◆ GetNext()

template<typename T >

template<typename Condition >

std::list< T >::iterator casacore::sisco::ConditionalQueue< T >::GetNext ( Condition & condition )

inlineprivate

Definition at line 121 of file ConditionalQueue.h.

References casacore::sisco::ConditionalQueue< T >::values_.

Referenced by casacore::sisco::ConditionalQueue< T >::PopIf().

◆ MaxSize()

template<typename T >

size_t casacore::sisco::ConditionalQueue< T >::MaxSize ( ) const

inline

Definition at line 117 of file ConditionalQueue.h.

References casacore::sisco::ConditionalQueue< T >::max_size_.

◆ NotifyOneChange()

template<typename T >

void casacore::sisco::ConditionalQueue< T >::NotifyOneChange ( )

inline

Notify the queue that the condition for values might have changed.

Definition at line 99 of file ConditionalQueue.h.

References casacore::sisco::ConditionalQueue< T >::push_condition_.

◆ PopIf()

template<typename T >

template<typename Condition >

bool casacore::sisco::ConditionalQueue< T >::PopIf	(	T &	result,
		std::unique_lock< std::mutex > &	lock,
		Condition	condition
	)

inline

Pop an object from the queue for which a specified condition holds.

The lock must be owned on entry and will be locked on exit, but may be temporary unlocked during the function.

The condition must be a callable function that takes a value as function parameter and returns a bool. The lock will always be owned when the condition function is called.

If this thread emptied the finished queue while another thread is waiting for a value, it needs to be notified to finish.

Definition at line 72 of file ConditionalQueue.h.

References casacore::sisco::ConditionalQueue< T >::GetNext(), casacore::sisco::ConditionalQueue< T >::is_finished_, casacore::sisco::ConditionalQueue< T >::pop_condition_, casacore::sisco::ConditionalQueue< T >::push_condition_, and casacore::sisco::ConditionalQueue< T >::values_.

◆ Push()

template<typename T >

void casacore::sisco::ConditionalQueue< T >::Push	(	T &&	value,
		std::unique_lock< std::mutex > &	lock
	)

inline

Place a new object at the end of the queue.

The lock must be owned on entry and will be locked on exit, but may be temporary unlocked during the function.

If the queue is full, the method will block until space is available.

We need to notify all, because if only one thread is awoken that is looking for a specific condition that is not met, the signal is lost while another nother thread's condition may be met.

Definition at line 34 of file ConditionalQueue.h.

References casacore::sisco::ConditionalQueue< T >::max_size_, casacore::sisco::ConditionalQueue< T >::pop_condition_, casacore::sisco::ConditionalQueue< T >::push_condition_, casacore::value(), and casacore::sisco::ConditionalQueue< T >::values_.

◆ Size()

template<typename T >

template<typename T >

std::list<T> casacore::sisco::ConditionalQueue< T >::values_

private

Definition at line 129 of file ConditionalQueue.h.

Referenced by casacore::sisco::ConditionalQueue< T >::Emplace(), casacore::sisco::ConditionalQueue< T >::GetNext(), casacore::sisco::ConditionalQueue< T >::PopIf(), casacore::sisco::ConditionalQueue< T >::Push(), and casacore::sisco::ConditionalQueue< T >::Size().

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

tables/AlternateMans/ConditionalQueue.h

Public Member Functions

Private Member Functions

Private Attributes

Detailed Description

Constructor & Destructor Documentation

◆ ConditionalQueue()

◆ ~ConditionalQueue()

Member Function Documentation

◆ Emplace()

◆ Finish()

◆ GetNext()

◆ MaxSize()

◆ NotifyOneChange()

◆ PopIf()

◆ Push()

◆ Size()

Member Data Documentation

◆ is_finished_

◆ max_size_

◆ pop_condition_

◆ push_condition_

◆ values_