mirror of https://github.com/stashapp/stash.git
61 lines
2.0 KiB
Go
61 lines
2.0 KiB
Go
// Copyright (c) 2022 Uber Technologies, Inc.
|
|
//
|
|
// Permission is hereby granted, free of charge, to any person obtaining a copy
|
|
// of this software and associated documentation files (the "Software"), to deal
|
|
// in the Software without restriction, including without limitation the rights
|
|
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
|
|
// copies of the Software, and to permit persons to whom the Software is
|
|
// furnished to do so, subject to the following conditions:
|
|
//
|
|
// The above copyright notice and this permission notice shall be included in
|
|
// all copies or substantial portions of the Software.
|
|
//
|
|
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
|
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
|
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
|
|
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
|
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
|
|
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
|
|
// THE SOFTWARE.
|
|
|
|
//go:build go1.18 && !go1.19
|
|
// +build go1.18,!go1.19
|
|
|
|
package atomic
|
|
|
|
import "unsafe"
|
|
|
|
type Pointer[T any] struct {
|
|
_ nocmp // disallow non-atomic comparison
|
|
p UnsafePointer
|
|
}
|
|
|
|
// NewPointer creates a new Pointer.
|
|
func NewPointer[T any](v *T) *Pointer[T] {
|
|
var p Pointer[T]
|
|
if v != nil {
|
|
p.p.Store(unsafe.Pointer(v))
|
|
}
|
|
return &p
|
|
}
|
|
|
|
// Load atomically loads the wrapped value.
|
|
func (p *Pointer[T]) Load() *T {
|
|
return (*T)(p.p.Load())
|
|
}
|
|
|
|
// Store atomically stores the passed value.
|
|
func (p *Pointer[T]) Store(val *T) {
|
|
p.p.Store(unsafe.Pointer(val))
|
|
}
|
|
|
|
// Swap atomically swaps the wrapped pointer and returns the old value.
|
|
func (p *Pointer[T]) Swap(val *T) (old *T) {
|
|
return (*T)(p.p.Swap(unsafe.Pointer(val)))
|
|
}
|
|
|
|
// CompareAndSwap is an atomic compare-and-swap.
|
|
func (p *Pointer[T]) CompareAndSwap(old, new *T) (swapped bool) {
|
|
return p.p.CompareAndSwap(unsafe.Pointer(old), unsafe.Pointer(new))
|
|
}
|