diff options
Diffstat (limited to 'src/leveldb/db/memtable.cc')
-rw-r--r-- | src/leveldb/db/memtable.cc | 68 |
1 files changed, 30 insertions, 38 deletions
diff --git a/src/leveldb/db/memtable.cc b/src/leveldb/db/memtable.cc index 287afdbdcb..00931d4671 100644 --- a/src/leveldb/db/memtable.cc +++ b/src/leveldb/db/memtable.cc @@ -18,20 +18,15 @@ static Slice GetLengthPrefixedSlice(const char* data) { return Slice(p, len); } -MemTable::MemTable(const InternalKeyComparator& cmp) - : comparator_(cmp), - refs_(0), - table_(comparator_, &arena_) { -} +MemTable::MemTable(const InternalKeyComparator& comparator) + : comparator_(comparator), refs_(0), table_(comparator_, &arena_) {} -MemTable::~MemTable() { - assert(refs_ == 0); -} +MemTable::~MemTable() { assert(refs_ == 0); } size_t MemTable::ApproximateMemoryUsage() { return arena_.MemoryUsage(); } -int MemTable::KeyComparator::operator()(const char* aptr, const char* bptr) - const { +int MemTable::KeyComparator::operator()(const char* aptr, + const char* bptr) const { // Internal keys are encoded as length-prefixed strings. Slice a = GetLengthPrefixedSlice(aptr); Slice b = GetLengthPrefixedSlice(bptr); @@ -48,39 +43,37 @@ static const char* EncodeKey(std::string* scratch, const Slice& target) { return scratch->data(); } -class MemTableIterator: public Iterator { +class MemTableIterator : public Iterator { public: - explicit MemTableIterator(MemTable::Table* table) : iter_(table) { } - - virtual bool Valid() const { return iter_.Valid(); } - virtual void Seek(const Slice& k) { iter_.Seek(EncodeKey(&tmp_, k)); } - virtual void SeekToFirst() { iter_.SeekToFirst(); } - virtual void SeekToLast() { iter_.SeekToLast(); } - virtual void Next() { iter_.Next(); } - virtual void Prev() { iter_.Prev(); } - virtual Slice key() const { return GetLengthPrefixedSlice(iter_.key()); } - virtual Slice value() const { + explicit MemTableIterator(MemTable::Table* table) : iter_(table) {} + + MemTableIterator(const MemTableIterator&) = delete; + MemTableIterator& operator=(const MemTableIterator&) = delete; + + ~MemTableIterator() override = default; + + bool Valid() const override { return iter_.Valid(); } + void Seek(const Slice& k) override { iter_.Seek(EncodeKey(&tmp_, k)); } + void SeekToFirst() override { iter_.SeekToFirst(); } + void SeekToLast() override { iter_.SeekToLast(); } + void Next() override { iter_.Next(); } + void Prev() override { iter_.Prev(); } + Slice key() const override { return GetLengthPrefixedSlice(iter_.key()); } + Slice value() const override { Slice key_slice = GetLengthPrefixedSlice(iter_.key()); return GetLengthPrefixedSlice(key_slice.data() + key_slice.size()); } - virtual Status status() const { return Status::OK(); } + Status status() const override { return Status::OK(); } private: MemTable::Table::Iterator iter_; - std::string tmp_; // For passing to EncodeKey - - // No copying allowed - MemTableIterator(const MemTableIterator&); - void operator=(const MemTableIterator&); + std::string tmp_; // For passing to EncodeKey }; -Iterator* MemTable::NewIterator() { - return new MemTableIterator(&table_); -} +Iterator* MemTable::NewIterator() { return new MemTableIterator(&table_); } -void MemTable::Add(SequenceNumber s, ValueType type, - const Slice& key, +void MemTable::Add(SequenceNumber s, ValueType type, const Slice& key, const Slice& value) { // Format of an entry is concatenation of: // key_size : varint32 of internal_key.size() @@ -90,9 +83,9 @@ void MemTable::Add(SequenceNumber s, ValueType type, size_t key_size = key.size(); size_t val_size = value.size(); size_t internal_key_size = key_size + 8; - const size_t encoded_len = - VarintLength(internal_key_size) + internal_key_size + - VarintLength(val_size) + val_size; + const size_t encoded_len = VarintLength(internal_key_size) + + internal_key_size + VarintLength(val_size) + + val_size; char* buf = arena_.Allocate(encoded_len); char* p = EncodeVarint32(buf, internal_key_size); memcpy(p, key.data(), key_size); @@ -121,10 +114,9 @@ bool MemTable::Get(const LookupKey& key, std::string* value, Status* s) { // all entries with overly large sequence numbers. const char* entry = iter.key(); uint32_t key_length; - const char* key_ptr = GetVarint32Ptr(entry, entry+5, &key_length); + const char* key_ptr = GetVarint32Ptr(entry, entry + 5, &key_length); if (comparator_.comparator.user_comparator()->Compare( - Slice(key_ptr, key_length - 8), - key.user_key()) == 0) { + Slice(key_ptr, key_length - 8), key.user_key()) == 0) { // Correct user key const uint64_t tag = DecodeFixed64(key_ptr + key_length - 8); switch (static_cast<ValueType>(tag & 0xff)) { |