cubefs

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// Copyright 2018 The CubeFS 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
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// implied. See the License for the specific language governing
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// permissions and limitations under the License.
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package fs
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import (
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	"sync"
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	"time"
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)
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// DentryCache defines the dentry cache.
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type DentryCache struct {
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	sync.Mutex
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	cache      map[string]uint64
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	expiration time.Time
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}
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// NewDentryCache returns a new dentry cache.
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func NewDentryCache() *DentryCache {
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	return &DentryCache{
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		cache:      make(map[string]uint64),
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		expiration: time.Now().Add(DentryValidDuration),
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	}
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}
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// Put puts an item into the cache.
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func (dc *DentryCache) Put(name string, ino uint64) {
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	if dc == nil {
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		return
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	}
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	dc.Lock()
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	defer dc.Unlock()
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	dc.cache[name] = ino
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	dc.expiration = time.Now().Add(DentryValidDuration)
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}
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// Get gets the item from the cache based on the given key.
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func (dc *DentryCache) Get(name string) (uint64, bool) {
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	if dc == nil {
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		return 0, false
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	}
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	dc.Lock()
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	defer dc.Unlock()
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	if dc.expiration.Before(time.Now()) {
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		dc.cache = make(map[string]uint64)
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		return 0, false
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	}
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	ino, ok := dc.cache[name]
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	return ino, ok
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}
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// Delete deletes the item based on the given key.
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func (dc *DentryCache) Delete(name string) {
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	if dc == nil {
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		return
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	}
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	dc.Lock()
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	defer dc.Unlock()
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	delete(dc.cache, name)
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}
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