ceph/src/rocksdb/db/version_builder.h

   1 //  Copyright (c) 2011-present, Facebook, Inc.  All rights reserved.
   2 //  This source code is licensed under both the GPLv2 (found in the
   3 //  COPYING file in the root directory) and Apache 2.0 License
   4 //  (found in the LICENSE.Apache file in the root directory).
   5 //
   6 // Copyright (c) 2011 The LevelDB Authors. All rights reserved.
   7 // Use of this source code is governed by a BSD-style license that can be
   8 // found in the LICENSE file. See the AUTHORS file for names of contributors.
   9 //
  10 #pragma once
  11
  12 #include <memory>
  13
  14 #include "rocksdb/file_system.h"
  15 #include "rocksdb/slice_transform.h"
  16
  17 namespace ROCKSDB_NAMESPACE {
  18
  19 struct ImmutableCFOptions;
  20 class TableCache;
  21 class VersionStorageInfo;
  22 class VersionEdit;
  23 struct FileMetaData;
  24 class InternalStats;
  25 class Version;
  26 class VersionSet;
  27 class ColumnFamilyData;
  28
  29 // A helper class so we can efficiently apply a whole sequence
  30 // of edits to a particular state without creating intermediate
  31 // Versions that contain full copies of the intermediate state.
  32 class VersionBuilder {
  33  public:
  34   VersionBuilder(const FileOptions& file_options,
  35                  const ImmutableCFOptions* ioptions, TableCache* table_cache,
  36                  VersionStorageInfo* base_vstorage, VersionSet* version_set);
  37   ~VersionBuilder();
  38
  39   bool CheckConsistencyForNumLevels();
  40   Status Apply(VersionEdit* edit);
  41   Status SaveTo(VersionStorageInfo* vstorage);
  42   Status LoadTableHandlers(InternalStats* internal_stats, int max_threads,
  43                            bool prefetch_index_and_filter_in_cache,
  44                            bool is_initial_load,
  45                            const SliceTransform* prefix_extractor,
  46                            size_t max_file_size_for_l0_meta_pin);
  47
  48  private:
  49   class Rep;
  50   std::unique_ptr<Rep> rep_;
  51 };
  52
  53 // A wrapper of version builder which references the current version in
  54 // constructor and unref it in the destructor.
  55 // Both of the constructor and destructor need to be called inside DB Mutex.
  56 class BaseReferencedVersionBuilder {
  57  public:
  58   explicit BaseReferencedVersionBuilder(ColumnFamilyData* cfd);
  59   BaseReferencedVersionBuilder(ColumnFamilyData* cfd, Version* v);
  60   ~BaseReferencedVersionBuilder();
  61   VersionBuilder* version_builder() const { return version_builder_.get(); }
  62
  63  private:
  64   std::unique_ptr<VersionBuilder> version_builder_;
  65   Version* version_;
  66 };
  67
  68 extern bool NewestFirstBySeqNo(FileMetaData* a, FileMetaData* b);
  69 }  // namespace ROCKSDB_NAMESPACE