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/**
* Copyright (C) 2014 MongoDB 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 <http://www.gnu.org/licenses/>.
*
* 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/exec/plan_stage.h"
#include "mongo/db/jsobj.h"
namespace mongo {
class OperationContext;
struct DeleteStageParams {
DeleteStageParams() : isMulti(false), shouldCallLogOp(false), fromMigrate(false) { }
// Should we delete all documents returned from the child (a "multi delete"), or at most one
// (a "single delete")?
bool isMulti;
// Should we write each delete to the oplog?
bool shouldCallLogOp;
// Is this delete part of a migrate operation that is essentially like a no-op
// when the cluster is observed by an external client.
bool fromMigrate;
};
/**
* This stage delete documents by DiskLoc that are returned from its child. NEED_TIME
* is returned after deleting a document.
*
* Callers of work() must be holding a write lock (and, for shouldCallLogOp=true deletes,
* callers must have had the replication coordinator approve the write).
*/
class DeleteStage : public PlanStage {
MONGO_DISALLOW_COPYING(DeleteStage);
public:
DeleteStage(OperationContext* txn,
const DeleteStageParams& params,
WorkingSet* ws,
Collection* collection,
PlanStage* child);
virtual ~DeleteStage();
virtual bool isEOF();
virtual StageState work(WorkingSetID* out);
virtual void saveState();
virtual void restoreState(OperationContext* opCtx);
virtual void invalidate(const DiskLoc& dl, InvalidationType type);
virtual std::vector<PlanStage*> getChildren() const;
virtual StageType stageType() const { return STAGE_DELETE; }
virtual PlanStageStats* getStats();
virtual const CommonStats* getCommonStats();
virtual const SpecificStats* getSpecificStats();
static const char* kStageType;
private:
// Transactional context. Not owned by us.
OperationContext* _txn;
DeleteStageParams _params;
// Not owned by us.
WorkingSet* _ws;
// Collection to operate on. Not owned by us. Can be NULL (if NULL, isEOF() will always
// return true). If non-NULL, the lifetime of the collection must supersede that of the
// stage.
Collection* _collection;
scoped_ptr<PlanStage> _child;
// Stats
CommonStats _commonStats;
DeleteStats _specificStats;
};
} // namespace mongo
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