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// Package abool provides atomic Boolean type for cleaner code and
// better performance.
package abool
import "sync/atomic"
// New creates an AtomicBool with default to false
func New() *AtomicBool {
return new(AtomicBool)
}
// NewBool creates an AtomicBool with given default value
func NewBool(ok bool) *AtomicBool {
ab := New()
if ok {
ab.Set()
}
return ab
}
// AtomicBool is an atomic Boolean
// Its methods are all atomic, thus safe to be called by
// multiple goroutines simultaneously
// Note: When embedding into a struct, one should always use
// *AtomicBool to avoid copy
type AtomicBool int32
// Set sets the Boolean to true
func (ab *AtomicBool) Set() {
atomic.StoreInt32((*int32)(ab), 1)
}
// UnSet sets the Boolean to false
func (ab *AtomicBool) UnSet() {
atomic.StoreInt32((*int32)(ab), 0)
}
// IsSet returns whether the Boolean is true
func (ab *AtomicBool) IsSet() bool {
return atomic.LoadInt32((*int32)(ab)) == 1
}
// SetTo sets the boolean with given Boolean
func (ab *AtomicBool) SetTo(yes bool) {
if yes {
atomic.StoreInt32((*int32)(ab), 1)
} else {
atomic.StoreInt32((*int32)(ab), 0)
}
}
// SetToIf sets the Boolean to new only if the Boolean matches the old
// Returns whether the set was done
func (ab *AtomicBool) SetToIf(old, new bool) (set bool) {
var o, n int32
if old {
o = 1
}
if new {
n = 1
}
return atomic.CompareAndSwapInt32((*int32)(ab), o, n)
}
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