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package atomics
import (
"sync/atomic"
"unsafe"
)
// {{ .Name }} provides user-friendly means of performing atomic operations on {{ .Type }} types.
type {{ .Name }} struct{ ptr unsafe.Pointer }
// New{{ .Name }} will return a new {{ .Name }} instance initialized with zero value.
func New{{ .Name }}() *{{ .Name }} {
var v {{ .Type }}
return &{{ .Name }}{
ptr: unsafe.Pointer(&v),
}
}
// Store will atomically store {{ .Type }} value in address contained within v.
func (v *{{ .Name }}) Store(val {{ .Type }}) {
atomic.StorePointer(&v.ptr, unsafe.Pointer(&val))
}
// Load will atomically load {{ .Type }} value at address contained within v.
func (v *{{ .Name }}) Load() {{ .Type }} {
return *(*{{ .Type }})(atomic.LoadPointer(&v.ptr))
}
// CAS performs a compare-and-swap for a(n) {{ .Type }} value at address contained within v.
func (v *{{ .Name }}) CAS(cmp, swp {{ .Type }}) bool {
for {
// Load current value at address
ptr := atomic.LoadPointer(&v.ptr)
cur := *(*{{ .Type }})(ptr)
// Perform comparison against current
if !({{ call .Compare "cur" "cmp" }}) {
return false
}
// Attempt to replace pointer
if atomic.CompareAndSwapPointer(
&v.ptr,
ptr,
unsafe.Pointer(&swp),
) {
return true
}
}
}
// Swap atomically stores new {{ .Type }} value into address contained within v, and returns previous value.
func (v *{{ .Name }}) Swap(swp {{ .Type }}) {{ .Type }} {
ptr := unsafe.Pointer(&swp)
ptr = atomic.SwapPointer(&v.ptr, ptr)
return *(*{{ .Type }})(ptr)
}
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