rocksdb/utilities/merge_operators/string_append/stringappend.h
Deon Nicholas accd3debbb Implemented StringAppendOperator and unit tests.
Summary:
Implemented the StringAppendOperator class (subclass of MergeOperator).
Found in utilities/merge_operators/string_append/stringappend.{h,cc}

It is a rocksdb Merge Operator that supports string/list concatenation
 with a configurable delimiter.

The tests are found in .../stringappend_test.cc. It implements a
 map : key -> (list of strings), with core operations Append(list_key,val)
 and Get(list_key).

Test Plan:
1. Navigate to your rocksdb repository
2. Execute: make stringappend_test  (to compile)
3. Execute: ./stringappend_test (to run the tests)
4. Execute: make all check (to test the ENTIRE rocksdb codebase / regression)

Reviewers: haobo, dhruba, zshao

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D10737
2013-05-13 15:09:42 -07:00

32 lines
759 B
C++

/**
* A MergeOperator for rocksdb/leveldb that implements string append.
* @author Deon Nicholas (dnicholas@fb.com)
* Copyright 2013 Facebook
*/
#include "leveldb/merge_operator.h"
#include "leveldb/slice.h"
namespace leveldb {
class StringAppendOperator : public MergeOperator {
public:
StringAppendOperator(char delim_char); /// Constructor: specify delimiter
virtual void 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