mirror of https://github.com/facebook/rocksdb.git
43 lines
1.4 KiB
C
43 lines
1.4 KiB
C
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// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
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// This source code is licensed under both the GPLv2 (found in the
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// COPYING file in the root directory) and Apache 2.0 License
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// (found in the LICENSE.Apache file in the root directory).
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#ifndef UTILITIES_MERGE_OPERATORS_BYTESXOR_H_
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#define UTILITIES_MERGE_OPERATORS_BYTESXOR_H_
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#include <algorithm>
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#include <memory>
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#include <string>
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#include "rocksdb/env.h"
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#include "rocksdb/merge_operator.h"
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#include "rocksdb/slice.h"
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#include "util/coding.h"
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#include "utilities/merge_operators.h"
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namespace rocksdb {
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// A 'model' merge operator that XORs two (same sized) array of bytes.
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// Implemented as an AssociativeMergeOperator for simplicity and example.
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class BytesXOROperator : public AssociativeMergeOperator {
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public:
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// XORs the two array of bytes one byte at a time and stores the result
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// in new_value. len is the number of xored bytes, and the length of new_value
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virtual bool Merge(const Slice& key,
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const Slice* existing_value,
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const Slice& value,
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std::string* new_value,
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Logger* logger) const override;
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virtual const char* Name() const override {
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return "BytesXOR";
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}
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void XOR(const Slice* existing_value, const Slice& value,
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std::string* new_value) const;
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};
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} // namespace rocksdb
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#endif // UTILITIES_MERGE_OPERATORS_BYTESXOR_H_
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