atomicbool

Documentation

Overview

Atomic store and load of bool type.

Copyright 2017 Nicolas S. Dade

bool-in-uint32 atomic store and load.

This type exists because of the aliasing of up to 3 other byte sized variables in the 4 bytes containing a regular Go 'bool' trips up the go -race detection, producing false races, because from Go's point of view we were reading and writing the 4 bytes, even though we were only, and atomically, changing only one.

Copyright 2021 Nicolas S. Dade

Index

• Constants
• func LoadBool(addr *bool) (val bool)
• func StoreBool(addr *bool, val bool)
• type Bool32
  • func (b *Bool32) CompareAndSwap(old, new bool) (swapped bool)
  • func (b *Bool32) Load() bool
  • func (b *Bool32) Store(x bool)

Constants

const (
	// True32 is the value of a Bool32 set to true. It's useful to initialize a Bool32 to true.
	True32 = Bool32(1)
)

Functions

func LoadBool

func LoadBool(addr *bool) (val bool)

func StoreBool

func StoreBool(addr *bool, val bool)

Types

type Bool32

type Bool32 uint32

Bool32 is a boolean stored in a uint32. It's sole purpose is to avoid go -race false positives which otherwise happen when a regular (1 byte) Go 'bool' is adjacent other variables in memory.

func (*Bool32) CompareAndSwap

func (b *Bool32) CompareAndSwap(old, new bool) (swapped bool)

CompareAndSwap atomically performs:

 if b == old {
   b = new
   return true
} else {

   return false
}

func (*Bool32) Load

func (b *Bool32) Load() bool

Load atomically loads and returns the boolean value of b

func (*Bool32) Store

func (b *Bool32) Store(x bool)

Store atomically stores x in b