mirror of https://github.com/k3s-io/k3s
56 lines
1.2 KiB
Go
56 lines
1.2 KiB
Go
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/*
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Copyright 2015 The Kubernetes Authors All rights reserved.
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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 proc
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import (
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"sync/atomic"
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)
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type stateType int32
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const (
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stateNew stateType = iota
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stateRunning
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stateTerminal
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)
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func (s *stateType) get() stateType {
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return stateType(atomic.LoadInt32((*int32)(s)))
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}
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func (s *stateType) transition(from, to stateType) bool {
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return atomic.CompareAndSwapInt32((*int32)(s), int32(from), int32(to))
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}
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func (s *stateType) transitionTo(to stateType, unless ...stateType) bool {
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if len(unless) == 0 {
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atomic.StoreInt32((*int32)(s), int32(to))
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return true
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}
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for {
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state := s.get()
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for _, x := range unless {
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if state == x {
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return false
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}
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}
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if s.transition(state, to) {
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return true
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}
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}
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}
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