mirror of https://github.com/k3s-io/k3s
63 lines
1.5 KiB
Go
63 lines
1.5 KiB
Go
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/*
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Copyright The containerd Authors.
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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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http://www.apache.org/licenses/LICENSE-2.0
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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 namedmutex provides NamedMutex that wraps sync.Mutex
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// and provides namespaced mutex.
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package namedmutex
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import (
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"sync"
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)
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// NamedMutex wraps sync.Mutex and provides namespaced mutex.
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type NamedMutex struct {
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muMap map[string]*sync.Mutex
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refMap map[string]int
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mu sync.Mutex
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}
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// Lock locks the mutex of the given name
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func (nl *NamedMutex) Lock(name string) {
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nl.mu.Lock()
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if nl.muMap == nil {
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nl.muMap = make(map[string]*sync.Mutex)
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}
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if nl.refMap == nil {
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nl.refMap = make(map[string]int)
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}
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if _, ok := nl.muMap[name]; !ok {
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nl.muMap[name] = &sync.Mutex{}
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}
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mu := nl.muMap[name]
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nl.refMap[name]++
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nl.mu.Unlock()
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mu.Lock()
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}
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// Unlock unlocks the mutex of the given name
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func (nl *NamedMutex) Unlock(name string) {
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nl.mu.Lock()
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mu := nl.muMap[name]
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nl.refMap[name]--
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if nl.refMap[name] <= 0 {
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delete(nl.muMap, name)
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delete(nl.refMap, name)
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}
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nl.mu.Unlock()
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mu.Unlock()
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}
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