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59 lines
2.0 KiB
Go
59 lines
2.0 KiB
Go
2 years ago
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// Copyright (c) 2021 Uber Technologies, Inc.
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//
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// Permission is hereby granted, free of charge, to any person obtaining a copy
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// of this software and associated documentation files (the "Software"), to deal
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// in the Software without restriction, including without limitation the rights
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// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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// copies of the Software, and to permit persons to whom the Software is
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// furnished to do so, subject to the following conditions:
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//
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// The above copyright notice and this permission notice shall be included in
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// all copies or substantial portions of the Software.
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//
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// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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// THE SOFTWARE.
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package atomic
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import (
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"sync/atomic"
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"unsafe"
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)
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// UnsafePointer is an atomic wrapper around unsafe.Pointer.
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type UnsafePointer struct {
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_ nocmp // disallow non-atomic comparison
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v unsafe.Pointer
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}
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// NewUnsafePointer creates a new UnsafePointer.
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func NewUnsafePointer(val unsafe.Pointer) *UnsafePointer {
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return &UnsafePointer{v: val}
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}
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// Load atomically loads the wrapped value.
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func (p *UnsafePointer) Load() unsafe.Pointer {
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return atomic.LoadPointer(&p.v)
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}
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// Store atomically stores the passed value.
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func (p *UnsafePointer) Store(val unsafe.Pointer) {
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atomic.StorePointer(&p.v, val)
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}
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// Swap atomically swaps the wrapped unsafe.Pointer and returns the old value.
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func (p *UnsafePointer) Swap(val unsafe.Pointer) (old unsafe.Pointer) {
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return atomic.SwapPointer(&p.v, val)
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}
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// CAS is an atomic compare-and-swap.
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func (p *UnsafePointer) CAS(old, new unsafe.Pointer) (swapped bool) {
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return atomic.CompareAndSwapPointer(&p.v, old, new)
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}
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