/**
* Copyright (C) 2013 10gen Inc.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License, version 3,
* as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see .
*
* As a special exception, the copyright holders give permission to link the
* code of portions of this program with the OpenSSL library under certain
* conditions as described in each individual source file and distribute
* linked combinations including the program with the OpenSSL library. You
* must comply with the GNU Affero General Public License in all respects for
* all of the code used other than as permitted herein. If you modify file(s)
* with this exception, you may extend this exception to your version of the
* file(s), but you are not obligated to do so. If you do not wish to do so,
* delete this exception statement from your version. If you delete this
* exception statement from all source files in the program, then also delete
* it in the license file.
*/
#pragma once
#include "mongo/db/storage/mmap_v1/diskloc.h"
#include "mongo/db/storage/record_store.h"
namespace mongo {
class SimpleRecordStoreV1;
/**
* This class iterates over a non-capped collection identified by 'ns'.
* The collection must exist when the constructor is called.
*
* If start is not DiskLoc(), the iteration begins at that DiskLoc.
*/
class SimpleRecordStoreV1Iterator final : public RecordCursor {
public:
SimpleRecordStoreV1Iterator( OperationContext* txn,
const SimpleRecordStoreV1* records,
bool forward);
boost::optional next() final;
boost::optional seekExact(const RecordId& id) final;
void savePositioned() final;
bool restore(OperationContext* txn) final;
void invalidate(const RecordId& dl) final;
std::unique_ptr fetcherForNext() const final;
std::unique_ptr fetcherForId(const RecordId& id) const final;
private:
void advance();
bool isEOF() { return _curr.isNull(); }
// for getNext, not owned
OperationContext* _txn;
// The result returned on the next call to getNext().
DiskLoc _curr;
const SimpleRecordStoreV1* const _recordStore;
const bool _forward;
};
} // namespace mongo