rocksdb/utilities/merge_operators/string_append/stringappend.h

32 lines
783 B
C++

/**
* A MergeOperator for rocksdb/leveldb that implements string append.
* @author Deon Nicholas (dnicholas@fb.com)
* Copyright 2013 Facebook
*/
#pragma once
#include "rocksdb/merge_operator.h"
#include "rocksdb/slice.h"
namespace leveldb {
class StringAppendOperator : public AssociativeMergeOperator {
public:
StringAppendOperator(char delim_char); /// Constructor: specify delimiter
virtual bool Merge(const Slice& key,
const Slice* existing_value,
const Slice& value,
std::string* new_value,
Logger* logger) const override;
virtual const char* Name() const override;
private:
char delim_; // The delimiter is inserted between elements
};
} // namespace leveldb