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-rw-r--r--vendor/github.com/golang/groupcache/lru/lru.go133
1 files changed, 0 insertions, 133 deletions
diff --git a/vendor/github.com/golang/groupcache/lru/lru.go b/vendor/github.com/golang/groupcache/lru/lru.go
deleted file mode 100644
index 532cc45e6..000000000
--- a/vendor/github.com/golang/groupcache/lru/lru.go
+++ /dev/null
@@ -1,133 +0,0 @@
-/*
-Copyright 2013 Google Inc.
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
- http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
-*/
-
-// Package lru implements an LRU cache.
-package lru
-
-import "container/list"
-
-// Cache is an LRU cache. It is not safe for concurrent access.
-type Cache struct {
- // MaxEntries is the maximum number of cache entries before
- // an item is evicted. Zero means no limit.
- MaxEntries int
-
- // OnEvicted optionally specificies a callback function to be
- // executed when an entry is purged from the cache.
- OnEvicted func(key Key, value interface{})
-
- ll *list.List
- cache map[interface{}]*list.Element
-}
-
-// A Key may be any value that is comparable. See http://golang.org/ref/spec#Comparison_operators
-type Key interface{}
-
-type entry struct {
- key Key
- value interface{}
-}
-
-// New creates a new Cache.
-// If maxEntries is zero, the cache has no limit and it's assumed
-// that eviction is done by the caller.
-func New(maxEntries int) *Cache {
- return &Cache{
- MaxEntries: maxEntries,
- ll: list.New(),
- cache: make(map[interface{}]*list.Element),
- }
-}
-
-// Add adds a value to the cache.
-func (c *Cache) Add(key Key, value interface{}) {
- if c.cache == nil {
- c.cache = make(map[interface{}]*list.Element)
- c.ll = list.New()
- }
- if ee, ok := c.cache[key]; ok {
- c.ll.MoveToFront(ee)
- ee.Value.(*entry).value = value
- return
- }
- ele := c.ll.PushFront(&entry{key, value})
- c.cache[key] = ele
- if c.MaxEntries != 0 && c.ll.Len() > c.MaxEntries {
- c.RemoveOldest()
- }
-}
-
-// Get looks up a key's value from the cache.
-func (c *Cache) Get(key Key) (value interface{}, ok bool) {
- if c.cache == nil {
- return
- }
- if ele, hit := c.cache[key]; hit {
- c.ll.MoveToFront(ele)
- return ele.Value.(*entry).value, true
- }
- return
-}
-
-// Remove removes the provided key from the cache.
-func (c *Cache) Remove(key Key) {
- if c.cache == nil {
- return
- }
- if ele, hit := c.cache[key]; hit {
- c.removeElement(ele)
- }
-}
-
-// RemoveOldest removes the oldest item from the cache.
-func (c *Cache) RemoveOldest() {
- if c.cache == nil {
- return
- }
- ele := c.ll.Back()
- if ele != nil {
- c.removeElement(ele)
- }
-}
-
-func (c *Cache) removeElement(e *list.Element) {
- c.ll.Remove(e)
- kv := e.Value.(*entry)
- delete(c.cache, kv.key)
- if c.OnEvicted != nil {
- c.OnEvicted(kv.key, kv.value)
- }
-}
-
-// Len returns the number of items in the cache.
-func (c *Cache) Len() int {
- if c.cache == nil {
- return 0
- }
- return c.ll.Len()
-}
-
-// Clear purges all stored items from the cache.
-func (c *Cache) Clear() {
- if c.OnEvicted != nil {
- for _, e := range c.cache {
- kv := e.Value.(*entry)
- c.OnEvicted(kv.key, kv.value)
- }
- }
- c.ll = nil
- c.cache = nil
-}