55 lines
1.3 KiB
Go
55 lines
1.3 KiB
Go
/*
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* Copyright 2020 The Dragonfly Authors
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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package atomiccount
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import (
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"sync/atomic"
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)
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// AtomicInt is a struct that can be added or subtracted atomically.
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type AtomicInt struct {
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count *int32
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}
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// NewAtomicInt returns a new AtomicInt.
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func NewAtomicInt(value int32) *AtomicInt {
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return &AtomicInt{
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count: &value,
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}
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}
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// Add atomically adds delta to count and returns the new value.
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func (ac *AtomicInt) Add(delta int32) int32 {
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if ac != nil {
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return atomic.AddInt32(ac.count, delta)
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}
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return 0
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}
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// Get the value atomically.
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func (ac *AtomicInt) Get() int32 {
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if ac != nil {
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return *ac.count
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}
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return 0
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}
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// Set to value atomically and returns the previous value.
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func (ac *AtomicInt) Set(value int32) int32 {
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return atomic.SwapInt32(ac.count, value)
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}
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