ion::SignalSource< T > Class Template Reference

Atomic signal source. More...

#include <ion/signal.hpp>

Public Types
using	ValueType = T

Public Member Functions
	SignalSource (ValueType initial=ValueType{}) noexcept
	Construct signal source.
	SignalSource (SignalSource const &)=delete
	SignalSource requires stable address so copy and move operations are disabled.
SignalSource &	operator= (SignalSource const &)=delete
auto	Load () const noexcept -> ValueType
	Load signal value.
void	Store (ValueType value) noexcept
	Store signal value.
auto	CompareExchangeWeak (ValueType &expected, ValueType desired) noexcept -> bool
	Set signal value using read-modify-write semantics.
auto	CompareExchangeStrong (ValueType &expected, ValueType desired) noexcept -> bool
	Set signal value using read-modify-write semantics.

Related Symbols
(Note that these are not member symbols.)
template<class T, class UnaryOperation>
auto	CompareExchangeTransform (SignalSource< T > &signal, UnaryOperation op) noexcept -> T
	Performs atomic compare-exchange transformation of signal value.

Detailed Description

template<class T>
class ion::SignalSource< T >

Atomic signal source.

See Signals for example.

Template Parameters

T	Value type of atomic signal. Must be trivial type and std::atomic<T>::is_always_lock_free == true.

Thread Safety

thread-safe

Constructor & Destructor Documentation

SignalSource()

template<class T>

ion::SignalSource< T >::SignalSource ( ValueType initial = ValueType{} )

explicitnoexcept

Construct signal source.

Parameters

initial

Initial value.

Member Function Documentation

CompareExchangeStrong()

template<class T>

auto ion::SignalSource< T >::CompareExchangeStrong ( ValueType & expected, ValueType desired ) -> bool

nodiscardnoexcept

Set signal value using read-modify-write semantics.

Parameters

[in,out]	expected	Reference to value expected to be found in the signal. This value is updated if the bitwise comparison failed.
[in]	desired	Desired value to write.

Returns

true if exchange was made.

false otherwise.

Memory Order

Relaxed memory order without any synchronization.

See also

CompareExchangeTransform()

CompareExchangeWeak()

template<class T>

auto ion::SignalSource< T >::CompareExchangeWeak ( ValueType & expected, ValueType desired ) -> bool

nodiscardnoexcept

Set signal value using read-modify-write semantics.

Note

Weak version is allowed to spuriously fail which will yield better performance on some platforms.

Parameters

[in,out]	expected	Reference to value expected to be found in the signal. This value is updated if the bitwise comparison failed.
[in]	desired	Value to write if expected value comparison succeeds.

Returns

true if exchange was made.

false otherwise.

Memory Order

Relaxed memory order without any synchronization.

See also

CompareExchangeTransform()

Load()

template<class T>

auto ion::SignalSource< T >::Load ( ) const -> ValueType

nodiscardnoexcept

Load signal value.

Returns

current value.

Memory Order

Relaxed memory order without any synchronization.

Store()

template<class T>

void ion::SignalSource< T >::Store ( ValueType value )

noexcept

Store signal value.

Parameters

value

New value to store.

Memory Order

Relaxed memory order without any synchronization.