46 lines
1.2 KiB
Go
46 lines
1.2 KiB
Go
// Copyright 2015 PingCAP, Inc.
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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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package util
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// Token is used as a permission to keep on running.
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type Token struct {
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}
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// TokenLimiter is used to limit the number of concurrent tasks.
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type TokenLimiter struct {
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count uint
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ch chan *Token
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}
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// Put releases the token.
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func (tl *TokenLimiter) Put(tk *Token) {
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tl.ch <- tk
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}
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// Get obtains a token.
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func (tl *TokenLimiter) Get() *Token {
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return <-tl.ch
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}
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// NewTokenLimiter creates a TokenLimiter with count tokens.
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func NewTokenLimiter(count uint) *TokenLimiter {
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tl := &TokenLimiter{count: count, ch: make(chan *Token, count)}
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for range count {
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tl.ch <- &Token{}
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}
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return tl
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}
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