YugabyteDB (2.13.0.0-b42, bfc6a6643e7399ac8a0e81d06a3ee6d6571b33ab)

// Copyright (c) YugaByte, Inc.

//

// Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except

// in compliance with the License.  You may obtain a copy of the License at

//

// http://www.apache.org/licenses/LICENSE-2.0

//

// Unless required by applicable law or agreed to in writing, software distributed under the License

// is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express

// or implied.  See the License for the specific language governing permissions and limitations

// under the License.

//

//

// Copyright (c) 2012 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.

#include "yb/rocksdb/table/fixed_size_filter_block.h"

#include "yb/rocksdb/filter_policy.h"

#include "yb/rocksdb/util/perf_context_imp.h"

namespace rocksdb {

namespace {

void AppendItem(std::string* props, const std::string& key,

                const std::string& value) {

  char cspace = ' ';

  std::string value_str("");

  size_t i = 0;

  const size_t dataLength = 64;

  const size_t tabLength = 2;

  const size_t offLength = 16;

  value_str.append(&value[i], std::min(size_t(dataLength), value.size()));

  i += dataLength;

  while (i < value.size()) {

    value_str.append("\n");

    value_str.append(offLength, cspace);

    value_str.append(&value[i], std::min(size_t(dataLength), value.size() - i));

    i += dataLength;

  }

  std::string result("");

  if (key.size() < (offLength - tabLength))

    result.append(size_t((offLength - tabLength)) - key.size(), cspace);

  result.append(key);

  props->append(result + ": " + value_str + "\n");

}

template <class TKey>

void AppendItem(std::string* props, const TKey& key, const std::string& value) {

  std::string key_str = rocksdb::ToString(key);

  AppendItem(props, key_str, value);

}

}  // namespace

// See doc/table_format.txt for an explanation of the filter block format.

// Generate new filter for fixed number of keys

FixedSizeFilterBlockBuilder::FixedSizeFilterBlockBuilder(

    const SliceTransform* prefix_extractor,

    const BlockBasedTableOptions& table_opt)

    : policy_(table_opt.filter_policy.get()),

      prefix_extractor_(prefix_extractor),

      whole_key_filtering_(table_opt.whole_key_filtering),

      bits_builder_(nullptr) {

}

void FixedSizeFilterBlockBuilder::StartBlock(uint64_t block_offset) {

  assert(policy_);

  assert(!bits_builder_);

  FilterBitsBuilder* filter_bits_builder_ = policy_->GetFilterBitsBuilder();

  assert(filter_bits_builder_);

  bits_builder_.reset(filter_bits_builder_);

}

void FixedSizeFilterBlockBuilder::Add(const Slice& key) {

  if (prefix_extractor_ && prefix_extractor_->InDomain(key)) {

    AddPrefix(key);

  }

  if (whole_key_filtering_) {

    AddKey(key);

  }

}

void FixedSizeFilterBlockBuilder::AddKey(const Slice& key) {

  assert(bits_builder_);

  bits_builder_->AddKey(key);

}

void FixedSizeFilterBlockBuilder::AddPrefix(const Slice& key) {

  assert(bits_builder_);

  Slice prefix = prefix_extractor_->Transform(key);

  bits_builder_->AddKey(prefix);

}

bool FixedSizeFilterBlockBuilder::ShouldFlush() const {

  assert(bits_builder_);

  return bits_builder_->IsFull();

}

Slice FixedSizeFilterBlockBuilder::Finish() {

  assert(bits_builder_);

  Slice finished_slice = bits_builder_->Finish(&active_block_data_);

  bits_builder_.reset();

  results_.push_back(std::move(active_block_data_));

  return finished_slice;

}

FixedSizeFilterBlockReader::FixedSizeFilterBlockReader(

    const SliceTransform* prefix_extractor,

    const BlockBasedTableOptions& table_opt,

    bool whole_key_filtering,

    BlockContents&& contents)

    : policy_(table_opt.filter_policy.get()),

      prefix_extractor_(prefix_extractor),

      whole_key_filtering_(whole_key_filtering),

      contents_(std::move(contents)) {

  assert(policy_);

  reader_.reset(policy_->GetFilterBitsReader(contents_.data));

}

bool FixedSizeFilterBlockReader::KeyMayMatch(const Slice& key, uint64_t block_offset) {

  return whole_key_filtering_ ? MayMatch(key) : true;

}

bool FixedSizeFilterBlockReader::PrefixMayMatch(const Slice& prefix, uint64_t block_offset) {

  return prefix_extractor_ ? MayMatch(prefix) : true;

}

bool FixedSizeFilterBlockReader::MayMatch(const Slice& entry) {

  if (reader_->MayMatch(entry)) {

    PERF_COUNTER_ADD(bloom_sst_hit_count, 1);

    return true;

  } else {

    PERF_COUNTER_ADD(bloom_sst_miss_count, 1);

    return false;

  }

}

size_t FixedSizeFilterBlockReader::ApproximateMemoryUsage() const {

  return contents_.data.size();

}

std::string FixedSizeFilterBlockReader::ToString() const {

  std::string result;

  result.reserve(contents_.data.size() * 2);

  AppendItem(&result, std::string("Filter block"), contents_.data.ToString(true));

  return result;

}

}  // namespace rocksdb