gf/container/gtype/float32.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 Float32 struct {
value uint32
}
// NewFloat32 returns a concurrent-safe object for float32 type,
// with given initial value <value>.
func NewFloat32(value ...float32) *Float32 {
if len(value) > 0 {
return &Float32{
value: math.Float32bits(value[0]),
}
}
return &Float32{}
}
// Clone clones and returns a new concurrent-safe object for float32 type.
func (v *Float32) Clone() *Float32 {
return NewFloat32(v.Val())
}
// Set atomically stores <value> into t.value and returns the previous value of t.value.
func (v *Float32) Set(value float32) (old float32) {
return math.Float32frombits(atomic.SwapUint32(&v.value, math.Float32bits(value)))
}
// Val atomically loads t.value.
func (v *Float32) Val() float32 {
return math.Float32frombits(atomic.LoadUint32(&v.value))
}
// Add atomically adds <delta> to t.value and returns the new value.
func (v *Float32) Add(delta float32) (new float32) {
for {
old := math.Float32frombits(v.value)
new = old + delta
if atomic.CompareAndSwapUint32(
(*uint32)(unsafe.Pointer(&v.value)),
math.Float32bits(old),
math.Float32bits(new),
) {
break
}
}
return
}
// Cas executes the compare-and-swap operation for value.
func (v *Float32) Cas(old, new float32) bool {
return atomic.CompareAndSwapUint32(&v.value, uint32(old), uint32(new))
}