git / moonbite-core / src/leveldb/db/version_edit.cc · raw
// 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 (const auto& deleted_file_kvp : deleted_files_) { PutVarint32(dst, kDeletedFile); PutVarint32(dst, deleted_file_kvp.first); // level PutVarint64(dst, deleted_file_kvp.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)) { return dst->DecodeFrom(str); } 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 = nullptr; uint32_t tag; // Temporary storage for parsing int level; uint64_t number; FileMetaData f; Slice str; InternalKey key; while (msg == nullptr && 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 == nullptr && !input.empty()) { msg = "invalid tag"; } Status result; if (msg != nullptr) { 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 (const auto& deleted_files_kvp : deleted_files_) { r.append("\n DeleteFile: "); AppendNumberTo(&r, deleted_files_kvp.first); r.append(" "); AppendNumberTo(&r, deleted_files_kvp.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