kcenon::thread::latch Class Reference

C++17-compatible latch implementation. More...

#include <synchronization.h>

Collaboration diagram for kcenon::thread::latch:

Public Member Functions
	latch (std::ptrdiff_t count)
	Constructs a latch with the given count.
void	count_down (std::ptrdiff_t n=1)
	Decrements the counter in a non-blocking manner.
bool	try_wait () const noexcept
	Tests if the internal counter equals zero.
void	wait () const
	Blocks until the counter reaches zero.
void	arrive_and_wait (std::ptrdiff_t n=1)
	Decrements the counter and blocks until it reaches zero.

Private Attributes
std::mutex	mutex_
std::condition_variable	cv_
std::ptrdiff_t	count_

Detailed Description

C++17-compatible latch implementation.

A downward counter which can be used to synchronize threads. The value of the counter is initialized on creation. Threads may block on the latch until the counter is decremented to zero.

Definition at line 39 of file synchronization.h.

Constructor & Destructor Documentation

latch()

kcenon::thread::latch::latch ( std::ptrdiff_t count )

inlineexplicit

Constructs a latch with the given count.

Parameters

count

The initial value of the counter (must be >= 0)

Definition at line 45 of file synchronization.h.

            : count_(count) {}

Member Function Documentation

arrive_and_wait()

void kcenon::thread::latch::arrive_and_wait ( std::ptrdiff_t n = 1 )

inline

Decrements the counter and blocks until it reaches zero.

Parameters

n	The value to subtract from the counter (default: 1)

Definition at line 81 of file synchronization.h.

                                                 {
            count_down(n);
            wait();
        }

References count_down(), and wait().

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count_down()

void kcenon::thread::latch::count_down ( std::ptrdiff_t n = 1 )

inline

Decrements the counter in a non-blocking manner.

Parameters

n	The value to subtract from the counter (default: 1)

Definition at line 52 of file synchronization.h.

                                            {
            std::unique_lock<std::mutex> lock(mutex_);
            count_ -= n;
            if (count_ <= 0) {
                cv_.notify_all();
            }
        }

References count_, cv_, and mutex_.

Referenced by arrive_and_wait().

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try_wait()

bool kcenon::thread::latch::try_wait ( ) const

inlinenoexcept

Tests if the internal counter equals zero.

Returns

true if the counter has reached zero, false otherwise

Definition at line 64 of file synchronization.h.

                                       {
            std::unique_lock<std::mutex> lock(mutex_);
            return count_ <= 0;
        }

References count_, and mutex_.

wait()

void kcenon::thread::latch::wait ( ) const

inline

Blocks until the counter reaches zero.

Definition at line 72 of file synchronization.h.

                          {
            std::unique_lock<std::mutex> lock(mutex_);
            cv_.wait(lock, [this] { return count_ <= 0; });
        }

References count_, cv_, and mutex_.

Referenced by arrive_and_wait().

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Member Data Documentation

count_

std::ptrdiff_t kcenon::thread::latch::count_

private

Definition at line 89 of file synchronization.h.

Referenced by count_down(), try_wait(), and wait().

cv_

std::condition_variable kcenon::thread::latch::cv_

mutableprivate

Definition at line 88 of file synchronization.h.

Referenced by count_down(), and wait().

mutex_

std::mutex kcenon::thread::latch::mutex_

mutableprivate

Definition at line 87 of file synchronization.h.

Referenced by count_down(), try_wait(), and wait().

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

• include/kcenon/thread/utils/synchronization.h