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-rw-r--r--vendor/cloud.google.com/go/internal/atomiccache/atomiccache.go58
1 files changed, 0 insertions, 58 deletions
diff --git a/vendor/cloud.google.com/go/internal/atomiccache/atomiccache.go b/vendor/cloud.google.com/go/internal/atomiccache/atomiccache.go
deleted file mode 100644
index 2bea8a150..000000000
--- a/vendor/cloud.google.com/go/internal/atomiccache/atomiccache.go
+++ /dev/null
@@ -1,58 +0,0 @@
-// Copyright 2016 Google Inc. All Rights Reserved.
-//
-// 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 atomiccache provides a map-based cache that supports very fast
-// reads.
-package atomiccache
-
-import (
- "sync"
- "sync/atomic"
-)
-
-type mapType map[interface{}]interface{}
-
-// Cache is a map-based cache that supports fast reads via use of atomics.
-// Writes are slow, requiring a copy of the entire cache.
-// The zero Cache is an empty cache, ready for use.
-type Cache struct {
- val atomic.Value // mapType
- mu sync.Mutex // used only by writers
-}
-
-// Get returns the value of the cache at key. If there is no value,
-// getter is called to provide one, and the cache is updated.
-// The getter function may be called concurrently. It should be pure,
-// returning the same value for every call.
-func (c *Cache) Get(key interface{}, getter func() interface{}) interface{} {
- mp, _ := c.val.Load().(mapType)
- if v, ok := mp[key]; ok {
- return v
- }
-
- // Compute value without lock.
- // Might duplicate effort but won't hold other computations back.
- newV := getter()
-
- c.mu.Lock()
- mp, _ = c.val.Load().(mapType)
- newM := make(mapType, len(mp)+1)
- for k, v := range mp {
- newM[k] = v
- }
- newM[key] = newV
- c.val.Store(newM)
- c.mu.Unlock()
- return newV
-}