seastar::expiring_fifo< T, OnExpiry, Clock > Class Template Reference

Detailed Description

template<typename T, typename OnExpiry = dummy_expiry<T>, typename Clock = lowres_clock>
class seastar::expiring_fifo< T, OnExpiry, Clock >

Container for elements with support for expiration of entries.

OnExpiry is a functor which will be called with a reference to T right before it expires. T is removed and destroyed from the container immediately after OnExpiry returns. OnExpiry callback must not modify the container, it can only modify its argument.

The container can only be moved before any elements are pushed.

#include <seastar/core/expiring_fifo.hh>

Public Types
using	clock = Clock
using	time_point = typename Clock::time_point

Public Member Functions
	expiring_fifo (OnExpiry on_expiry) noexcept(std::is_nothrow_move_constructible_v< OnExpiry >)
	expiring_fifo (expiring_fifo &&o) noexcept
expiring_fifo &	operator= (expiring_fifo &&o) noexcept
bool	empty () const noexcept
	operator bool () const noexcept
	Equivalent to !empty()
T &	front () noexcept
const T &	front () const noexcept
size_t	size () const noexcept
void	reserve (size_t size)
void	push_back (const T &payload)
void	push_back (T &&payload)
void	push_back (T &&payload, time_point timeout)
void	pop_front () noexcept

Member Function Documentation

empty()

template<typename T , typename OnExpiry = dummy_expiry<T>, typename Clock = lowres_clock>

bool seastar::expiring_fifo< T, OnExpiry, Clock >::empty ( ) const

inlinenoexcept

Checks if container contains any elements

Note

Inside OnExpiry callback, the expired element is still contained.

Returns

true if and only if there are any elements contained.

front() [1/2]

template<typename T , typename OnExpiry = dummy_expiry<T>, typename Clock = lowres_clock>

const T& seastar::expiring_fifo< T, OnExpiry, Clock >::front ( ) const

inlinenoexcept

Returns a reference to the element in the front. Valid only when !empty().

front() [2/2]

template<typename T , typename OnExpiry = dummy_expiry<T>, typename Clock = lowres_clock>

T& seastar::expiring_fifo< T, OnExpiry, Clock >::front ( )

inlinenoexcept

Returns a reference to the element in the front. Valid only when !empty().

pop_front()

template<typename T , typename OnExpiry = dummy_expiry<T>, typename Clock = lowres_clock>

void seastar::expiring_fifo< T, OnExpiry, Clock >::pop_front ( )

inlinenoexcept

Removes the element at the front. Can be called only if !empty().

push_back() [1/3]

template<typename T , typename OnExpiry = dummy_expiry<T>, typename Clock = lowres_clock>

void seastar::expiring_fifo< T, OnExpiry, Clock >::push_back ( const T &  payload )

inline

Adds element to the back of the queue. The element will never expire.

push_back() [2/3]

template<typename T , typename OnExpiry = dummy_expiry<T>, typename Clock = lowres_clock>

void seastar::expiring_fifo< T, OnExpiry, Clock >::push_back ( T &&  payload )

inline

Adds element to the back of the queue. The element will never expire.

push_back() [3/3]

template<typename T , typename OnExpiry = dummy_expiry<T>, typename Clock = lowres_clock>

void seastar::expiring_fifo< T, OnExpiry, Clock >::push_back ( T &&  payload, time_point  timeout  )

inline

Adds element to the back of the queue. The element will expire when timeout is reached, unless it is time_point::max(), in which case it never expires.

reserve()

template<typename T , typename OnExpiry = dummy_expiry<T>, typename Clock = lowres_clock>

void seastar::expiring_fifo< T, OnExpiry, Clock >::reserve ( size_t  size )

inline

Reserves storage in the container for at least 'size' elements. Note that expired elements may also take space when they are not in the front of the queue.

Doesn't give any guarantees about exception safety of subsequent push_back().

size()

template<typename T , typename OnExpiry = dummy_expiry<T>, typename Clock = lowres_clock>

size_t seastar::expiring_fifo< T, OnExpiry, Clock >::size ( ) const

inlinenoexcept

Returns the number of elements contained.

Note

Expired elements are not contained. Expiring element is still contained when OnExpiry is called.

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

• seastar/core/expiring_fifo.hh