1 | // Copyright (c) 2011 The LevelDB Authors. All rights reserved. |
2 | // Use of this source code is governed by a BSD-style license that can be |
3 | // found in the LICENSE file. See the AUTHORS file for names of contributors. |
4 | |
5 | #ifndef STORAGE_LEVELDB_DB_VERSION_EDIT_H_ |
6 | #define STORAGE_LEVELDB_DB_VERSION_EDIT_H_ |
7 | |
8 | #include <set> |
9 | #include <utility> |
10 | #include <vector> |
11 | |
12 | #include "db/dbformat.h" |
13 | |
14 | namespace leveldb { |
15 | |
16 | class VersionSet; |
17 | |
18 | struct FileMetaData { |
19 | FileMetaData() : refs(0), allowed_seeks(1 << 30), file_size(0) {} |
20 | |
21 | int refs; |
22 | int allowed_seeks; // Seeks allowed until compaction |
23 | uint64_t number; |
24 | uint64_t file_size; // File size in bytes |
25 | InternalKey smallest; // Smallest internal key served by table |
26 | InternalKey largest; // Largest internal key served by table |
27 | }; |
28 | |
29 | class VersionEdit { |
30 | public: |
31 | VersionEdit() { Clear(); } |
32 | ~VersionEdit() = default; |
33 | |
34 | void Clear(); |
35 | |
36 | void SetComparatorName(const Slice& name) { |
37 | has_comparator_ = true; |
38 | comparator_ = name.ToString(); |
39 | } |
40 | void SetLogNumber(uint64_t num) { |
41 | has_log_number_ = true; |
42 | log_number_ = num; |
43 | } |
44 | void SetPrevLogNumber(uint64_t num) { |
45 | has_prev_log_number_ = true; |
46 | prev_log_number_ = num; |
47 | } |
48 | void SetNextFile(uint64_t num) { |
49 | has_next_file_number_ = true; |
50 | next_file_number_ = num; |
51 | } |
52 | void SetLastSequence(SequenceNumber seq) { |
53 | has_last_sequence_ = true; |
54 | last_sequence_ = seq; |
55 | } |
56 | void SetCompactPointer(int level, const InternalKey& key) { |
57 | compact_pointers_.push_back(std::make_pair(level, key)); |
58 | } |
59 | |
60 | // Add the specified file at the specified number. |
61 | // REQUIRES: This version has not been saved (see VersionSet::SaveTo) |
62 | // REQUIRES: "smallest" and "largest" are smallest and largest keys in file |
63 | void AddFile(int level, uint64_t file, uint64_t file_size, |
64 | const InternalKey& smallest, const InternalKey& largest) { |
65 | FileMetaData f; |
66 | f.number = file; |
67 | f.file_size = file_size; |
68 | f.smallest = smallest; |
69 | f.largest = largest; |
70 | new_files_.push_back(std::make_pair(level, f)); |
71 | } |
72 | |
73 | // Delete the specified "file" from the specified "level". |
74 | void RemoveFile(int level, uint64_t file) { |
75 | deleted_files_.insert(std::make_pair(level, file)); |
76 | } |
77 | |
78 | void EncodeTo(std::string* dst) const; |
79 | Status DecodeFrom(const Slice& src); |
80 | |
81 | std::string DebugString() const; |
82 | |
83 | private: |
84 | friend class VersionSet; |
85 | |
86 | typedef std::set<std::pair<int, uint64_t>> DeletedFileSet; |
87 | |
88 | std::string comparator_; |
89 | uint64_t log_number_; |
90 | uint64_t prev_log_number_; |
91 | uint64_t next_file_number_; |
92 | SequenceNumber last_sequence_; |
93 | bool has_comparator_; |
94 | bool has_log_number_; |
95 | bool has_prev_log_number_; |
96 | bool has_next_file_number_; |
97 | bool has_last_sequence_; |
98 | |
99 | std::vector<std::pair<int, InternalKey>> compact_pointers_; |
100 | DeletedFileSet deleted_files_; |
101 | std::vector<std::pair<int, FileMetaData>> new_files_; |
102 | }; |
103 | |
104 | } // namespace leveldb |
105 | |
106 | #endif // STORAGE_LEVELDB_DB_VERSION_EDIT_H_ |
107 | |