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 #include "db/dbformat.h" 12 13 namespace leveldb { 14 15 class VersionSet; 16 17 struct FileMetaData { 18 int refs; 19 int allowed_seeks; // Seeks allowed until compaction 20 uint64_t number; 21 uint64_t file_size; // File size in bytes 22 InternalKey smallest; // Smallest internal key served by table 23 InternalKey largest; // Largest internal key served by table 24 FileMetaDataFileMetaData25 FileMetaData() : refs(0), allowed_seeks(1 << 30), file_size(0) { } 26 }; 27 28 class VersionEdit { 29 public: VersionEdit()30 VersionEdit() { Clear(); } ~VersionEdit()31 ~VersionEdit() { } 32 33 void Clear(); 34 SetComparatorName(const Slice & name)35 void SetComparatorName(const Slice& name) { 36 has_comparator_ = true; 37 comparator_ = name.ToString(); 38 } SetLogNumber(uint64_t num)39 void SetLogNumber(uint64_t num) { 40 has_log_number_ = true; 41 log_number_ = num; 42 } SetPrevLogNumber(uint64_t num)43 void SetPrevLogNumber(uint64_t num) { 44 has_prev_log_number_ = true; 45 prev_log_number_ = num; 46 } SetNextFile(uint64_t num)47 void SetNextFile(uint64_t num) { 48 has_next_file_number_ = true; 49 next_file_number_ = num; 50 } SetLastSequence(SequenceNumber seq)51 void SetLastSequence(SequenceNumber seq) { 52 has_last_sequence_ = true; 53 last_sequence_ = seq; 54 } SetCompactPointer(int level,const InternalKey & key)55 void SetCompactPointer(int level, const InternalKey& key) { 56 compact_pointers_.push_back(std::make_pair(level, key)); 57 } 58 59 // Add the specified file at the specified number. 60 // REQUIRES: This version has not been saved (see VersionSet::SaveTo) 61 // REQUIRES: "smallest" and "largest" are smallest and largest keys in file AddFile(int level,uint64_t file,uint64_t file_size,const InternalKey & smallest,const InternalKey & largest)62 void AddFile(int level, uint64_t file, 63 uint64_t file_size, 64 const InternalKey& smallest, 65 const InternalKey& largest) { 66 FileMetaData f; 67 f.number = file; 68 f.file_size = file_size; 69 f.smallest = smallest; 70 f.largest = largest; 71 new_files_.push_back(std::make_pair(level, f)); 72 } 73 74 // Delete the specified "file" from the specified "level". DeleteFile(int level,uint64_t file)75 void DeleteFile(int level, uint64_t file) { 76 deleted_files_.insert(std::make_pair(level, file)); 77 } 78 79 void EncodeTo(std::string* dst) const; 80 Status DecodeFrom(const Slice& src); 81 82 std::string DebugString() const; 83 84 private: 85 friend class VersionSet; 86 87 typedef std::set< std::pair<int, uint64_t> > DeletedFileSet; 88 89 std::string comparator_; 90 uint64_t log_number_; 91 uint64_t prev_log_number_; 92 uint64_t next_file_number_; 93 SequenceNumber last_sequence_; 94 bool has_comparator_; 95 bool has_log_number_; 96 bool has_prev_log_number_; 97 bool has_next_file_number_; 98 bool has_last_sequence_; 99 100 std::vector< std::pair<int, InternalKey> > compact_pointers_; 101 DeletedFileSet deleted_files_; 102 std::vector< std::pair<int, FileMetaData> > new_files_; 103 }; 104 105 } // namespace leveldb 106 107 #endif // STORAGE_LEVELDB_DB_VERSION_EDIT_H_ 108