rocksdb/util/user_comparator_wrapper.h
sdong fdf882ded2 Replace namespace name "rocksdb" with ROCKSDB_NAMESPACE (#6433)
Summary:
When dynamically linking two binaries together, different builds of RocksDB from two sources might cause errors. To provide a tool for user to solve the problem, the RocksDB namespace is changed to a flag which can be overridden in build time.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6433

Test Plan: Build release, all and jtest. Try to build with ROCKSDB_NAMESPACE with another flag.

Differential Revision: D19977691

fbshipit-source-id: aa7f2d0972e1c31d75339ac48478f34f6cfcfb3e
2020-02-20 12:09:57 -08:00

66 lines
2.2 KiB
C++

// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
// This source code is licensed under both the GPLv2 (found in the
// COPYING file in the root directory) and Apache 2.0 License
// (found in the LICENSE.Apache file in the root directory).
// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file. See the AUTHORS file for names of contributors.
#pragma once
#include "monitoring/perf_context_imp.h"
#include "rocksdb/comparator.h"
namespace ROCKSDB_NAMESPACE {
// Wrapper of user comparator, with auto increment to
// perf_context.user_key_comparison_count.
class UserComparatorWrapper final : public Comparator {
public:
explicit UserComparatorWrapper(const Comparator* const user_cmp)
: user_comparator_(user_cmp) {}
~UserComparatorWrapper() = default;
const Comparator* user_comparator() const { return user_comparator_; }
int Compare(const Slice& a, const Slice& b) const override {
PERF_COUNTER_ADD(user_key_comparison_count, 1);
return user_comparator_->Compare(a, b);
}
bool Equal(const Slice& a, const Slice& b) const override {
PERF_COUNTER_ADD(user_key_comparison_count, 1);
return user_comparator_->Equal(a, b);
}
const char* Name() const override { return user_comparator_->Name(); }
void FindShortestSeparator(std::string* start,
const Slice& limit) const override {
return user_comparator_->FindShortestSeparator(start, limit);
}
void FindShortSuccessor(std::string* key) const override {
return user_comparator_->FindShortSuccessor(key);
}
const Comparator* GetRootComparator() const override {
return user_comparator_->GetRootComparator();
}
bool IsSameLengthImmediateSuccessor(const Slice& s,
const Slice& t) const override {
return user_comparator_->IsSameLengthImmediateSuccessor(s, t);
}
bool CanKeysWithDifferentByteContentsBeEqual() const override {
return user_comparator_->CanKeysWithDifferentByteContentsBeEqual();
}
private:
const Comparator* user_comparator_;
};
} // namespace ROCKSDB_NAMESPACE