Summary: Added necessary routines for dumping block based SST with block filter Test Plan: Added "raw" mode to utility sst_dump Reviewers: sdong, rven Reviewed By: rven Subscribers: dhruba Differential Revision: https://reviews.facebook.net/D29679
105 lines
4.1 KiB
C++
105 lines
4.1 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.
|
|
//
|
|
// 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.
|
|
//
|
|
// A filter block is stored near the end of a Table file. It contains
|
|
// filters (e.g., bloom filters) for all data blocks in the table combined
|
|
// into a single filter block.
|
|
|
|
#pragma once
|
|
|
|
#include <stddef.h>
|
|
#include <stdint.h>
|
|
#include <string>
|
|
#include <memory>
|
|
#include <vector>
|
|
#include "rocksdb/options.h"
|
|
#include "rocksdb/slice.h"
|
|
#include "rocksdb/slice_transform.h"
|
|
#include "table/filter_block.h"
|
|
#include "util/hash.h"
|
|
|
|
namespace rocksdb {
|
|
|
|
|
|
// A BlockBasedFilterBlockBuilder is used to construct all of the filters for a
|
|
// particular Table. It generates a single string which is stored as
|
|
// a special block in the Table.
|
|
//
|
|
// The sequence of calls to BlockBasedFilterBlockBuilder must match the regexp:
|
|
// (StartBlock Add*)* Finish
|
|
class BlockBasedFilterBlockBuilder : public FilterBlockBuilder {
|
|
public:
|
|
BlockBasedFilterBlockBuilder(const SliceTransform* prefix_extractor,
|
|
const BlockBasedTableOptions& table_opt);
|
|
|
|
virtual bool IsBlockBased() override { return true; }
|
|
virtual void StartBlock(uint64_t block_offset) override;
|
|
virtual void Add(const Slice& key) override;
|
|
virtual Slice Finish() override;
|
|
|
|
private:
|
|
void AddKey(const Slice& key);
|
|
void AddPrefix(const Slice& key);
|
|
void GenerateFilter();
|
|
|
|
// important: all of these might point to invalid addresses
|
|
// at the time of destruction of this filter block. destructor
|
|
// should NOT dereference them.
|
|
const FilterPolicy* policy_;
|
|
const SliceTransform* prefix_extractor_;
|
|
bool whole_key_filtering_;
|
|
|
|
std::string entries_; // Flattened entry contents
|
|
std::vector<size_t> start_; // Starting index in entries_ of each entry
|
|
uint32_t added_to_start_; // To indicate if key is added
|
|
std::string result_; // Filter data computed so far
|
|
std::vector<Slice> tmp_entries_; // policy_->CreateFilter() argument
|
|
std::vector<uint32_t> filter_offsets_;
|
|
|
|
// No copying allowed
|
|
BlockBasedFilterBlockBuilder(const BlockBasedFilterBlockBuilder&);
|
|
void operator=(const BlockBasedFilterBlockBuilder&);
|
|
};
|
|
|
|
// A FilterBlockReader is used to parse filter from SST table.
|
|
// KeyMayMatch and PrefixMayMatch would trigger filter checking
|
|
class BlockBasedFilterBlockReader : public FilterBlockReader {
|
|
public:
|
|
// REQUIRES: "contents" and *policy must stay live while *this is live.
|
|
BlockBasedFilterBlockReader(const SliceTransform* prefix_extractor,
|
|
const BlockBasedTableOptions& table_opt,
|
|
BlockContents&& contents);
|
|
virtual bool IsBlockBased() override { return true; }
|
|
virtual bool KeyMayMatch(const Slice& key,
|
|
uint64_t block_offset = kNotValid) override;
|
|
virtual bool PrefixMayMatch(const Slice& prefix,
|
|
uint64_t block_offset = kNotValid) override;
|
|
virtual size_t ApproximateMemoryUsage() const override;
|
|
|
|
// convert this object to a human readable form
|
|
std::string ToString() const override;
|
|
|
|
private:
|
|
const FilterPolicy* policy_;
|
|
const SliceTransform* prefix_extractor_;
|
|
bool whole_key_filtering_;
|
|
const char* data_; // Pointer to filter data (at block-start)
|
|
const char* offset_; // Pointer to beginning of offset array (at block-end)
|
|
size_t num_; // Number of entries in offset array
|
|
size_t base_lg_; // Encoding parameter (see kFilterBaseLg in .cc file)
|
|
BlockContents contents_;
|
|
|
|
bool MayMatch(const Slice& entry, uint64_t block_offset);
|
|
|
|
// No copying allowed
|
|
BlockBasedFilterBlockReader(const BlockBasedFilterBlockReader&);
|
|
void operator=(const BlockBasedFilterBlockReader&);
|
|
};
|
|
} // namespace rocksdb
|