rocksdb/table/cuckoo_table_builder.h

97 lines
3.2 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.
#pragma once
#ifndef ROCKSDB_LITE
#include <stdint.h>
#include <string>
#include <vector>
#include "rocksdb/status.h"
#include "table/table_builder.h"
#include "rocksdb/table.h"
#include "rocksdb/table_properties.h"
#include "util/autovector.h"
namespace rocksdb {
struct CuckooBucket {
CuckooBucket(): is_empty(true) {}
Slice key;
Slice value;
bool is_empty;
};
class CuckooTableBuilder: public TableBuilder {
public:
CuckooTableBuilder(
WritableFile* file, unsigned int fixed_key_length,
unsigned int fixed_value_length, double hash_table_ratio,
unsigned int file_size, unsigned int max_num_hash_table,
unsigned int max_search_depth,
unsigned int (*GetSliceHash)(const Slice&, unsigned int,
unsigned int));
// REQUIRES: Either Finish() or Abandon() has been called.
~CuckooTableBuilder();
// Add key,value to the table being constructed.
// REQUIRES: key is after any previously added key according to comparator.
// REQUIRES: Finish(), Abandon() have not been called
void Add(const Slice& key, const Slice& value) override;
// Return non-ok iff some error has been detected.
Status status() const override;
// Finish building the table. Stops using the file passed to the
// constructor after this function returns.
// REQUIRES: Finish(), Abandon() have not been called
Status Finish() override;
// Indicate that the contents of this builder should be abandoned. Stops
// using the file passed to the constructor after this function returns.
// If the caller is not going to call Finish(), it must call Abandon()
// before destroying this builder.
// REQUIRES: Finish(), Abandon() have not been called
void Abandon() override;
// Number of calls to Add() so far.
uint64_t NumEntries() const override;
// Size of the file generated so far. If invoked after a successful
// Finish() call, returns the size of the final generated file.
uint64_t FileSize() const override;
private:
bool MakeSpaceForKey(const Slice& key, unsigned int* bucket_id,
autovector<unsigned int> hash_vals);
unsigned int num_hash_table_;
WritableFile* file_;
const unsigned int value_length_;
const unsigned int bucket_size_;
const double hash_table_ratio_;
const unsigned int max_num_buckets_;
const unsigned int max_num_hash_table_;
const unsigned int max_search_depth_;
Status status_;
std::vector<CuckooBucket> buckets_;
bool is_last_level_file_ = true;
TableProperties properties_;
unsigned int (*GetSliceHash)(const Slice& s, unsigned int index,
unsigned int max_num_buckets);
std::string unused_user_key_ = "";
std::string prev_key_;
bool closed_ = false; // Either Finish() or Abandon() has been called.
// No copying allowed
CuckooTableBuilder(const CuckooTableBuilder&) = delete;
void operator=(const CuckooTableBuilder&) = delete;
};
} // namespace rocksdb
#endif // ROCKSDB_LITE