mirror of
https://github.com/facebook/rocksdb.git
synced 2024-11-30 04:41:49 +00:00
9cd221094c
Summary: Add appropriate LICENSE and Copyright message. Test Plan: make check Reviewers: CC: Task ID: # Blame Rev:
54 lines
1.7 KiB
C++
54 lines
1.7 KiB
C++
// Copyright (c) 2013, Facebook, Inc. All rights reserved.
|
|
// This source code is licensed under the BSD-style license found in the
|
|
// LICENSE file in the root directory of this source tree. An additional grant
|
|
// of patent rights can be found in the PATENTS file in the same directory.
|
|
//
|
|
/**
|
|
* Back-end implementation details specific to the Merge Operator.
|
|
*/
|
|
|
|
#include "rocksdb/merge_operator.h"
|
|
|
|
namespace rocksdb {
|
|
|
|
// Given a "real" merge from the library, call the user's
|
|
// associative merge function one-by-one on each of the operands.
|
|
// NOTE: It is assumed that the client's merge-operator will handle any errors.
|
|
bool AssociativeMergeOperator::FullMerge(
|
|
const Slice& key,
|
|
const Slice* existing_value,
|
|
const std::deque<std::string>& operand_list,
|
|
std::string* new_value,
|
|
Logger* logger) const {
|
|
|
|
// Simply loop through the operands
|
|
Slice temp_existing;
|
|
std::string temp_value;
|
|
for (const auto& operand : operand_list) {
|
|
Slice value(operand);
|
|
if (!Merge(key, existing_value, value, &temp_value, logger)) {
|
|
return false;
|
|
}
|
|
swap(temp_value, *new_value);
|
|
temp_existing = Slice(*new_value);
|
|
existing_value = &temp_existing;
|
|
}
|
|
|
|
// The result will be in *new_value. All merges succeeded.
|
|
return true;
|
|
}
|
|
|
|
// Call the user defined simple merge on the operands;
|
|
// NOTE: It is assumed that the client's merge-operator will handle any errors.
|
|
bool AssociativeMergeOperator::PartialMerge(
|
|
const Slice& key,
|
|
const Slice& left_operand,
|
|
const Slice& right_operand,
|
|
std::string* new_value,
|
|
Logger* logger) const {
|
|
|
|
return Merge(key, &left_operand, right_operand, new_value, logger);
|
|
}
|
|
|
|
} // namespace rocksdb
|