signal.hpp File Reference

ion::{SignalSource, SignalToken} and algorithms More...

#include <atomic>
#include <cassert>
#include <cstdint>
#include <optional>
#include <tuple>
#include <type_traits>
#include <ion/detail/macros.hpp>

Go to the source code of this file.

Classes
class	ion::SignalSource< T >
	Atomic signal source. More...
class	ion::SignalToken< T >
	Signal token that has an associated SignalSource and last known value. More...
struct	ion::Status< T >
	Represents signal source previous (old) and current (new) value. More...
struct	ion::WaitAnyResult< T1, T2 >
	Represents wait result from one of multiple possible signals. More...
struct	ion::StatusTag
	Select algorithm overload that returns signal status. More...
struct	ion::DifferenceTag
	Select algorithm overload that returns signal difference. More...

Functions
template<class T, class UnaryOperation>
auto	ion::CompareExchangeTransform (SignalSource< T > &signal, UnaryOperation op) noexcept -> T
	Performs atomic compare-exchange transformation of signal value.
template<class T>
constexpr auto	ion::operator== (SignalToken< T > const &lhs, SignalToken< T > const &rhs) noexcept -> bool
	Equality comparison.
template<class T>
constexpr auto	ion::operator!= (SignalToken< T > const &lhs, SignalToken< T > const &rhs) noexcept -> bool
	Inequality comparison.
Wait and yield current signal value.
template<class T>
auto	ion::Wait (SignalToken< T > &token) noexcept -> T
	Wait until signal source changes and return current value.
template<class T, class Predicate>
auto	ion::Wait (SignalToken< T > &token, Predicate &&stop_waiting) noexcept -> T
	Wait with predicate.
Wait and yield Status<T>.
template<class T>
auto	ion::Wait (StatusTag, SignalToken< T > &token) noexcept -> Status< T >
	Wait until signal source changes and return current and previous values.
template<class T, class Predicate>
auto	ion::Wait (StatusTag, SignalToken< T > &token, Predicate &&stop_waiting) noexcept -> Status< T >
	Wait with predicate.
Wait and yield changes since last.
template<class T>
auto	ion::Wait (DifferenceTag, SignalToken< T > &token) noexcept -> T
	Wait until signal source changes and return difference (current - previous) value.
template<class T, class Predicate>
auto	ion::Wait (DifferenceTag, SignalToken< T > &token, Predicate &&stop_waiting) noexcept -> T
	Wait until signal source changes and return difference (current - previous) value.
Wait for either of two signals.
Effects Load and compare each of the signals with previous value. The first one to change will be recorded in the WaitAnyResult::index. Depending on the selected overload the result of WaitAnyResult::result is either the current, difference or the Status containing both previous and current value.
template<class T1, class T2>
auto	ion::WaitAny (SignalToken< T1 > &token1, SignalToken< T2 > &token2) noexcept -> WaitAnyResult< T1, T2 >
	Wait for either of two signals to change.
template<class T1, class T2>
auto	ion::WaitAny (StatusTag, SignalToken< T1 > &token1, SignalToken< T2 > &token2) noexcept -> WaitAnyResult< Status< T1 >, Status< T2 > >
	Wait for either of two signals to change.
template<class T1, class T2>
auto	ion::WaitAny (DifferenceTag, SignalToken< T1 > &token1, SignalToken< T2 > &token2) noexcept -> WaitAnyResult< T1, T2 >
	Wait for either of two signals to change.

Variables
Tag-invoke types
constexpr StatusTag	ion::status_tag {}
	Constant instance of StatusTag.
constexpr DifferenceTag	ion::difference_tag {}
	Constant instance of DifferenceTag.

Detailed Description

ion::{SignalSource, SignalToken} and algorithms

Copyright

SPDX-FileCopyrightText: 2023-2025 European Southern Observatory (ESO)

SPDX-License-Identifier: LGPL-3.0-only