rocksdb/db/table_cache.h
Haobo Xu bdf1085944 [RocksDB] cleanup EnvOptions
Summary:
This diff simplifies EnvOptions by treating it as POD, similar to Options.
- virtual functions are removed and member fields are accessed directly.
- StorageOptions is removed.
- Options.allow_readahead and Options.allow_readahead_compactions are deprecated.
- Unused global variables are removed: useOsBuffer, useFsReadAhead, useMmapRead, useMmapWrite

Test Plan: make check; db_stress

Reviewers: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11175
2013-06-12 11:17:19 -07:00

71 lines
2.4 KiB
C++

// 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)
#ifndef STORAGE_LEVELDB_DB_TABLE_CACHE_H_
#define STORAGE_LEVELDB_DB_TABLE_CACHE_H_
#include <string>
#include <stdint.h>
#include "db/dbformat.h"
#include "leveldb/env.h"
#include "leveldb/cache.h"
#include "port/port.h"
#include "table/table.h"
namespace leveldb {
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,
Table** tableptr = 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* tableIO);
// 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* tableIO = nullptr);
};
} // namespace leveldb
#endif // STORAGE_LEVELDB_DB_TABLE_CACHE_H_