rocksdb/utilities/blob_db/blob_db_iterator.h

105 lines
2.3 KiB
C++

// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
// 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
#ifndef ROCKSDB_LITE
#include "rocksdb/iterator.h"
#include "utilities/blob_db/blob_db_impl.h"
namespace rocksdb {
namespace blob_db {
using rocksdb::ManagedSnapshot;
class BlobDBIterator : public Iterator {
public:
BlobDBIterator(ManagedSnapshot* snapshot, ArenaWrappedDBIter* iter,
BlobDBImpl* blob_db)
: snapshot_(snapshot), iter_(iter), blob_db_(blob_db) {}
virtual ~BlobDBIterator() = default;
bool Valid() const override {
if (!iter_->Valid()) {
return false;
}
return status_.ok();
}
Status status() const override {
if (!iter_->status().ok()) {
return iter_->status();
}
return status_;
}
void SeekToFirst() override {
iter_->SeekToFirst();
UpdateBlobValue();
}
void SeekToLast() override {
iter_->SeekToLast();
UpdateBlobValue();
}
void Seek(const Slice& target) override {
iter_->Seek(target);
UpdateBlobValue();
}
void SeekForPrev(const Slice& target) override {
iter_->SeekForPrev(target);
UpdateBlobValue();
}
void Next() override {
assert(Valid());
iter_->Next();
UpdateBlobValue();
}
void Prev() override {
assert(Valid());
iter_->Prev();
UpdateBlobValue();
}
Slice key() const override {
assert(Valid());
return iter_->key();
}
Slice value() const override {
assert(Valid());
if (!iter_->IsBlob()) {
return iter_->value();
}
return value_;
}
// Iterator::Refresh() not supported.
private:
void UpdateBlobValue() {
TEST_SYNC_POINT("BlobDBIterator::UpdateBlobValue:Start:1");
TEST_SYNC_POINT("BlobDBIterator::UpdateBlobValue:Start:2");
value_.Reset();
if (iter_->Valid() && iter_->IsBlob()) {
status_ = blob_db_->GetBlobValue(iter_->key(), iter_->value(), &value_);
}
}
std::unique_ptr<ManagedSnapshot> snapshot_;
std::unique_ptr<ArenaWrappedDBIter> iter_;
BlobDBImpl* blob_db_;
Status status_;
PinnableSlice value_;
};
} // namespace blob_db
} // namespace rocksdb
#endif // !ROCKSDB_LITE