gf/container/gtype/float64.go
2019-07-29 21:01:19 +08:00

65 lines
1.6 KiB
Go

// Copyright 2018 gf Author(https://github.com/gogf/gf). All Rights Reserved.
//
// This Source Code Form is subject to the terms of the MIT License.
// If a copy of the MIT was not distributed with this file,
// You can obtain one at https://github.com/gogf/gf.
package gtype
import (
"math"
"sync/atomic"
"unsafe"
)
type Float64 struct {
value uint64
}
// NewFloat64 returns a concurrent-safe object for float64 type,
// with given initial value <value>.
func NewFloat64(value ...float64) *Float64 {
if len(value) > 0 {
return &Float64{
value: math.Float64bits(value[0]),
}
}
return &Float64{}
}
// Clone clones and returns a new concurrent-safe object for float64 type.
func (v *Float64) Clone() *Float64 {
return NewFloat64(v.Val())
}
// Set atomically stores <value> into t.value and returns the previous value of t.value.
func (v *Float64) Set(value float64) (old float64) {
return math.Float64frombits(atomic.SwapUint64(&v.value, math.Float64bits(value)))
}
// Val atomically loads t.value.
func (v *Float64) Val() float64 {
return math.Float64frombits(atomic.LoadUint64(&v.value))
}
// Add atomically adds <delta> to t.value and returns the new value.
func (v *Float64) Add(delta float64) (new float64) {
for {
old := math.Float64frombits(v.value)
new = old + delta
if atomic.CompareAndSwapUint64(
(*uint64)(unsafe.Pointer(&v.value)),
math.Float64bits(old),
math.Float64bits(new),
) {
break
}
}
return
}
// Cas executes the compare-and-swap operation for value.
func (v *Float64) Cas(old, new float64) bool {
return atomic.CompareAndSwapUint64(&v.value, uint64(old), uint64(new))
}