rocksdb/table/table_iterator.h

70 lines
2.3 KiB
C++

// Copyright (c) Meta Platforms, Inc. and affiliates.
//
// This source code is licensed under both the GPLv2 (found in the
// COPYING file in the root directory) and Apache 2.0 License
// (found in the LICENSE.Apache file in the root directory).
#pragma once
#include "rocksdb/iterator.h"
#include "table/internal_iterator.h"
namespace ROCKSDB_NAMESPACE {
// An iterator wrapper class used to wrap an `InternalIterator` created by API
// `TableReader::NewIterator`. The `InternalIterator` should be allocated with
// the default allocator, not on an arena.
// NOTE: Callers should ensure the wrapped `InternalIterator*` is a valid
// pointer before constructing a `TableIterator` with it.
class TableIterator : public Iterator {
void reset(InternalIterator* iter) noexcept {
if (iter_ != nullptr) {
delete iter_;
}
iter_ = iter;
}
public:
explicit TableIterator(InternalIterator* iter) : iter_(iter) {}
TableIterator(const TableIterator&) = delete;
TableIterator& operator=(const TableIterator&) = delete;
TableIterator(TableIterator&& o) noexcept {
iter_ = o.iter_;
o.iter_ = nullptr;
}
TableIterator& operator=(TableIterator&& o) noexcept {
reset(o.iter_);
o.iter_ = nullptr;
return *this;
}
InternalIterator* operator->() { return iter_; }
InternalIterator* get() { return iter_; }
~TableIterator() override { reset(nullptr); }
bool Valid() const override { return iter_->Valid(); }
void SeekToFirst() override { return iter_->SeekToFirst(); }
void SeekToLast() override { return iter_->SeekToLast(); }
void Seek(const Slice& target) override { return iter_->Seek(target); }
void SeekForPrev(const Slice& target) override {
return iter_->SeekForPrev(target);
}
void Next() override { return iter_->Next(); }
void Prev() override { return iter_->Prev(); }
Slice key() const override { return iter_->key(); }
Slice value() const override { return iter_->value(); }
Status status() const override { return iter_->status(); }
Status GetProperty(std::string /*prop_name*/,
std::string* /*prop*/) override {
assert(false);
return Status::NotSupported("TableIterator does not support GetProperty.");
}
private:
InternalIterator* iter_;
};
} // namespace ROCKSDB_NAMESPACE