| // 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. |
| |
| #include "db/version_edit.h" |
| |
| #include "db/version_set.h" |
| #include "util/coding.h" |
| |
| namespace leveldb { |
| |
| // Tag numbers for serialized VersionEdit. These numbers are written to |
| // disk and should not be changed. |
| enum Tag { |
| kComparator = 1, |
| kLogNumber = 2, |
| kNextFileNumber = 3, |
| kLastSequence = 4, |
| kCompactPointer = 5, |
| kDeletedFile = 6, |
| kNewFile = 7, |
| // 8 was used for large value refs |
| kPrevLogNumber = 9 |
| }; |
| |
| void VersionEdit::Clear() { |
| comparator_.clear(); |
| log_number_ = 0; |
| prev_log_number_ = 0; |
| last_sequence_ = 0; |
| next_file_number_ = 0; |
| has_comparator_ = false; |
| has_log_number_ = false; |
| has_prev_log_number_ = false; |
| has_next_file_number_ = false; |
| has_last_sequence_ = false; |
| deleted_files_.clear(); |
| new_files_.clear(); |
| } |
| |
| void VersionEdit::EncodeTo(std::string* dst) const { |
| if (has_comparator_) { |
| PutVarint32(dst, kComparator); |
| PutLengthPrefixedSlice(dst, comparator_); |
| } |
| if (has_log_number_) { |
| PutVarint32(dst, kLogNumber); |
| PutVarint64(dst, log_number_); |
| } |
| if (has_prev_log_number_) { |
| PutVarint32(dst, kPrevLogNumber); |
| PutVarint64(dst, prev_log_number_); |
| } |
| if (has_next_file_number_) { |
| PutVarint32(dst, kNextFileNumber); |
| PutVarint64(dst, next_file_number_); |
| } |
| if (has_last_sequence_) { |
| PutVarint32(dst, kLastSequence); |
| PutVarint64(dst, last_sequence_); |
| } |
| |
| for (size_t i = 0; i < compact_pointers_.size(); i++) { |
| PutVarint32(dst, kCompactPointer); |
| PutVarint32(dst, compact_pointers_[i].first); // level |
| PutLengthPrefixedSlice(dst, compact_pointers_[i].second.Encode()); |
| } |
| |
| for (DeletedFileSet::const_iterator iter = deleted_files_.begin(); |
| iter != deleted_files_.end(); |
| ++iter) { |
| PutVarint32(dst, kDeletedFile); |
| PutVarint32(dst, iter->first); // level |
| PutVarint64(dst, iter->second); // file number |
| } |
| |
| for (size_t i = 0; i < new_files_.size(); i++) { |
| const FileMetaData& f = new_files_[i].second; |
| PutVarint32(dst, kNewFile); |
| PutVarint32(dst, new_files_[i].first); // level |
| PutVarint64(dst, f.number); |
| PutVarint64(dst, f.file_size); |
| PutLengthPrefixedSlice(dst, f.smallest.Encode()); |
| PutLengthPrefixedSlice(dst, f.largest.Encode()); |
| } |
| } |
| |
| static bool GetInternalKey(Slice* input, InternalKey* dst) { |
| Slice str; |
| if (GetLengthPrefixedSlice(input, &str)) { |
| dst->DecodeFrom(str); |
| return true; |
| } else { |
| return false; |
| } |
| } |
| |
| static bool GetLevel(Slice* input, int* level) { |
| uint32_t v; |
| if (GetVarint32(input, &v) && |
| v < config::kNumLevels) { |
| *level = v; |
| return true; |
| } else { |
| return false; |
| } |
| } |
| |
| Status VersionEdit::DecodeFrom(const Slice& src) { |
| Clear(); |
| Slice input = src; |
| const char* msg = NULL; |
| uint32_t tag; |
| |
| // Temporary storage for parsing |
| int level; |
| uint64_t number; |
| FileMetaData f; |
| Slice str; |
| InternalKey key; |
| |
| while (msg == NULL && GetVarint32(&input, &tag)) { |
| switch (tag) { |
| case kComparator: |
| if (GetLengthPrefixedSlice(&input, &str)) { |
| comparator_ = str.ToString(); |
| has_comparator_ = true; |
| } else { |
| msg = "comparator name"; |
| } |
| break; |
| |
| case kLogNumber: |
| if (GetVarint64(&input, &log_number_)) { |
| has_log_number_ = true; |
| } else { |
| msg = "log number"; |
| } |
| break; |
| |
| case kPrevLogNumber: |
| if (GetVarint64(&input, &prev_log_number_)) { |
| has_prev_log_number_ = true; |
| } else { |
| msg = "previous log number"; |
| } |
| break; |
| |
| case kNextFileNumber: |
| if (GetVarint64(&input, &next_file_number_)) { |
| has_next_file_number_ = true; |
| } else { |
| msg = "next file number"; |
| } |
| break; |
| |
| case kLastSequence: |
| if (GetVarint64(&input, &last_sequence_)) { |
| has_last_sequence_ = true; |
| } else { |
| msg = "last sequence number"; |
| } |
| break; |
| |
| case kCompactPointer: |
| if (GetLevel(&input, &level) && |
| GetInternalKey(&input, &key)) { |
| compact_pointers_.push_back(std::make_pair(level, key)); |
| } else { |
| msg = "compaction pointer"; |
| } |
| break; |
| |
| case kDeletedFile: |
| if (GetLevel(&input, &level) && |
| GetVarint64(&input, &number)) { |
| deleted_files_.insert(std::make_pair(level, number)); |
| } else { |
| msg = "deleted file"; |
| } |
| break; |
| |
| case kNewFile: |
| if (GetLevel(&input, &level) && |
| GetVarint64(&input, &f.number) && |
| GetVarint64(&input, &f.file_size) && |
| GetInternalKey(&input, &f.smallest) && |
| GetInternalKey(&input, &f.largest)) { |
| new_files_.push_back(std::make_pair(level, f)); |
| } else { |
| msg = "new-file entry"; |
| } |
| break; |
| |
| default: |
| msg = "unknown tag"; |
| break; |
| } |
| } |
| |
| if (msg == NULL && !input.empty()) { |
| msg = "invalid tag"; |
| } |
| |
| Status result; |
| if (msg != NULL) { |
| result = Status::Corruption("VersionEdit", msg); |
| } |
| return result; |
| } |
| |
| std::string VersionEdit::DebugString() const { |
| std::string r; |
| r.append("VersionEdit {"); |
| if (has_comparator_) { |
| r.append("\n Comparator: "); |
| r.append(comparator_); |
| } |
| if (has_log_number_) { |
| r.append("\n LogNumber: "); |
| AppendNumberTo(&r, log_number_); |
| } |
| if (has_prev_log_number_) { |
| r.append("\n PrevLogNumber: "); |
| AppendNumberTo(&r, prev_log_number_); |
| } |
| if (has_next_file_number_) { |
| r.append("\n NextFile: "); |
| AppendNumberTo(&r, next_file_number_); |
| } |
| if (has_last_sequence_) { |
| r.append("\n LastSeq: "); |
| AppendNumberTo(&r, last_sequence_); |
| } |
| for (size_t i = 0; i < compact_pointers_.size(); i++) { |
| r.append("\n CompactPointer: "); |
| AppendNumberTo(&r, compact_pointers_[i].first); |
| r.append(" "); |
| r.append(compact_pointers_[i].second.DebugString()); |
| } |
| for (DeletedFileSet::const_iterator iter = deleted_files_.begin(); |
| iter != deleted_files_.end(); |
| ++iter) { |
| r.append("\n DeleteFile: "); |
| AppendNumberTo(&r, iter->first); |
| r.append(" "); |
| AppendNumberTo(&r, iter->second); |
| } |
| for (size_t i = 0; i < new_files_.size(); i++) { |
| const FileMetaData& f = new_files_[i].second; |
| r.append("\n AddFile: "); |
| AppendNumberTo(&r, new_files_[i].first); |
| r.append(" "); |
| AppendNumberTo(&r, f.number); |
| r.append(" "); |
| AppendNumberTo(&r, f.file_size); |
| r.append(" "); |
| r.append(f.smallest.DebugString()); |
| r.append(" .. "); |
| r.append(f.largest.DebugString()); |
| } |
| r.append("\n}\n"); |
| return r; |
| } |
| |
| } // namespace leveldb |