rocksdb/table/cuckoo/cuckoo_table_reader.h

101 lines
3.4 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
#ifndef ROCKSDB_LITE
#include <string>
#include <memory>
#include <utility>
#include <vector>
#include "file/random_access_file_reader.h"
#include "rocksdb/env.h"
#include "rocksdb/options.h"
#include "table/table_reader.h"
namespace ROCKSDB_NAMESPACE {
class Arena;
class TableReader;
struct ImmutableOptions;
class CuckooTableReader: public TableReader {
public:
CuckooTableReader(const ImmutableOptions& ioptions,
std::unique_ptr<RandomAccessFileReader>&& file,
uint64_t file_size, const Comparator* user_comparator,
uint64_t (*get_slice_hash)(const Slice&, uint32_t,
uint64_t));
~CuckooTableReader() {}
std::shared_ptr<const TableProperties> GetTableProperties() const override {
return table_props_;
}
Status status() const { return status_; }
Status Get(const ReadOptions& readOptions, const Slice& key,
GetContext* get_context, const SliceTransform* prefix_extractor,
bool skip_filters = false) override;
// Returns a new iterator over table contents
// compaction_readahead_size: its value will only be used if for_compaction =
// true
InternalIterator* NewIterator(const ReadOptions&,
const SliceTransform* prefix_extractor,
Arena* arena, bool skip_filters,
TableReaderCaller caller,
size_t compaction_readahead_size = 0,
bool allow_unprepared_value = false) override;
void Prepare(const Slice& target) override;
// Report an approximation of how much memory has been used.
size_t ApproximateMemoryUsage() const override;
// Following methods are not implemented for Cuckoo Table Reader
uint64_t ApproximateOffsetOf(const Slice& /*key*/,
TableReaderCaller /*caller*/) override {
return 0;
}
uint64_t ApproximateSize(const Slice& /*start*/, const Slice& /*end*/,
TableReaderCaller /*caller*/) override {
return 0;
}
void SetupForCompaction() override {}
// End of methods not implemented.
private:
friend class CuckooTableIterator;
void LoadAllKeys(std::vector<std::pair<Slice, uint32_t>>* key_to_bucket_id);
std::unique_ptr<RandomAccessFileReader> file_;
Slice file_data_;
bool is_last_level_;
bool identity_as_first_hash_;
bool use_module_hash_;
std::shared_ptr<const TableProperties> table_props_;
Status status_;
uint32_t num_hash_func_;
std::string unused_key_;
uint32_t key_length_;
uint32_t user_key_length_;
uint32_t value_length_;
uint32_t bucket_length_;
uint32_t cuckoo_block_size_;
uint32_t cuckoo_block_bytes_minus_one_;
uint64_t table_size_;
const Comparator* ucomp_;
uint64_t (*get_slice_hash_)(const Slice& s, uint32_t index,
uint64_t max_num_buckets);
};
} // namespace ROCKSDB_NAMESPACE
#endif // ROCKSDB_LITE