rocksdb/db/table_cache.h
Siying Dong f03b2df010 Follow-up Cleaning-up After D13521
Summary:
This patch is to address @haobo's comments on D13521:
1. rename Table to be TableReader and make its factory function to be GetTableReader
2. move the compression type selection logic out of TableBuilder but to compaction logic
3. more accurate comments
4. Move stat name constants into BlockBasedTable implementation.
5. remove some uncleaned codes in simple_table_db_test

Test Plan: pass test suites.

Reviewers: haobo, dhruba, kailiu

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13785
2013-10-30 10:52:33 -07:00

79 lines
3 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) 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.
//
// Thread-safe (provides internal synchronization)
#pragma once
#include <string>
#include <stdint.h>
#include "db/dbformat.h"
#include "rocksdb/env.h"
#include "rocksdb/cache.h"
#include "port/port.h"
#include "rocksdb/table.h"
namespace rocksdb {
class Env;
class TableCache {
public:
TableCache(const std::string& dbname, const Options* options,
const EnvOptions& storage_options, int entries);
~TableCache();
// Return an iterator for the specified file number (the corresponding
// file length must be exactly "file_size" bytes). If "tableptr" is
// non-nullptr, also sets "*tableptr" to point to the Table object
// underlying the returned iterator, or nullptr if no Table object underlies
// the returned iterator. The returned "*tableptr" object is owned by
// the cache and should not be deleted, and is valid for as long as the
// returned iterator is live.
Iterator* NewIterator(const ReadOptions& options,
const EnvOptions& toptions,
uint64_t file_number,
uint64_t file_size,
TableReader** table_reader_ptr = nullptr,
bool for_compaction = false);
// If a seek to internal key "k" in specified file finds an entry,
// call (*handle_result)(arg, found_key, found_value) repeatedly until
// it returns false.
Status Get(const ReadOptions& options,
uint64_t file_number,
uint64_t file_size,
const Slice& k,
void* arg,
bool (*handle_result)(void*, const Slice&, const Slice&, bool),
bool* table_io,
void (*mark_key_may_exist)(void*) = nullptr);
// Determine whether the table may contain the specified prefix. If
// the table index of blooms are not in memory, this may cause an I/O
bool PrefixMayMatch(const ReadOptions& options, uint64_t file_number,
uint64_t file_size, const Slice& internal_prefix,
bool* table_io);
// Evict any entry for the specified file number
void Evict(uint64_t file_number);
private:
Env* const env_;
const std::string dbname_;
const Options* options_;
const EnvOptions& storage_options_;
std::shared_ptr<Cache> cache_;
Status FindTable(const EnvOptions& toptions, uint64_t file_number,
uint64_t file_size, Cache::Handle**, bool* table_io=nullptr,
const bool no_io = false);
};
} // namespace rocksdb