58 lines
1.6 KiB
Go
58 lines
1.6 KiB
Go
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// Copyright 2015 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 kv
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import "bytes"
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// Key represents high-level Key type.
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type Key []byte
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// Next returns the next key in byte-order.
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func (k Key) Next() Key {
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// add 0x0 to the end of key
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buf := make([]byte, len([]byte(k))+1)
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copy(buf, []byte(k))
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return buf
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}
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// Cmp returns the comparison result of two key.
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// The result will be 0 if a==b, -1 if a < b, and +1 if a > b.
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func (k Key) Cmp(another Key) int {
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return bytes.Compare(k, another)
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}
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// HasPrefix tests whether the Key begins with prefix.
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func (k Key) HasPrefix(prefix Key) bool {
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return bytes.HasPrefix(k, prefix)
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}
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// Clone returns a copy of the Key.
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func (k Key) Clone() Key {
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return append([]byte(nil), k...)
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}
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// EncodedKey represents encoded key in low-level storage engine.
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type EncodedKey []byte
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// Cmp returns the comparison result of two key.
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// The result will be 0 if a==b, -1 if a < b, and +1 if a > b.
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func (k EncodedKey) Cmp(another EncodedKey) int {
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return bytes.Compare(k, another)
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}
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// Next returns the next key in byte-order.
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func (k EncodedKey) Next() EncodedKey {
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return EncodedKey(bytes.Join([][]byte{k, Key{0}}, nil))
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}
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