41 lines
1.1 KiB
Go
41 lines
1.1 KiB
Go
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// Copyright 2015 Google Inc. All Rights Reserved.
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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 freelist
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import "unsafe"
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// A freelist for arbitrary pointers. Not safe for concurrent access.
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type Freelist struct {
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list []unsafe.Pointer
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}
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// Get an element from the freelist, returning nil if empty.
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func (fl *Freelist) Get() (p unsafe.Pointer) {
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l := len(fl.list)
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if l == 0 {
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return
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}
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p = fl.list[l-1]
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fl.list = fl.list[:l-1]
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return
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}
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// Contribute an element back to the freelist.
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func (fl *Freelist) Put(p unsafe.Pointer) {
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fl.list = append(fl.list, p)
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}
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