57 lines
1.3 KiB
Go
57 lines
1.3 KiB
Go
// Copyright 2017 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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// See the License for the specific language governing permissions and
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// limitations under the License.
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package kvenc
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import (
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"sync/atomic"
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"github.com/pingcap/tidb/meta/autoid"
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)
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var _ autoid.Allocator = &allocator{}
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var (
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step = int64(5000)
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)
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// NewAllocator new an allocator.
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func NewAllocator() autoid.Allocator {
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return &allocator{}
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}
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type allocator struct {
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base int64
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}
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func (alloc *allocator) Alloc(tableID int64) (int64, error) {
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return atomic.AddInt64(&alloc.base, 1), nil
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}
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func (alloc *allocator) Rebase(tableID, newBase int64, allocIDs bool) error {
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atomic.StoreInt64(&alloc.base, newBase)
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return nil
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}
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func (alloc *allocator) Base() int64 {
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return atomic.LoadInt64(&alloc.base)
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}
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func (alloc *allocator) End() int64 {
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return alloc.Base() + step
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}
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func (alloc *allocator) NextGlobalAutoID(tableID int64) (int64, error) {
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return alloc.End() + 1, nil
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}
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