This iterator will go over the collection twice - once going forward (first extent -> last extent) and once backwards in an attempt to salvage potentially corrupted or unreachable records. More...

#include <record_store_v1_repair_iterator.h>

Inheritance diagram for mongo::RecordStoreV1RepairCursor:

Detailed Description

This iterator will go over the collection twice - once going forward (first extent -> last extent) and once backwards in an attempt to salvage potentially corrupted or unreachable records.

It is used by the mongodump –repair option.

Public Member Functions
	RecordStoreV1RepairCursor (OperationContext opCtx, const RecordStoreV1Base recordStore)

boost::optional< Record >	next () final
	Moves forward and returns the new data or boost::none if there is no more data. More...

void	invalidate (OperationContext *opCtx, const RecordId &dl)
	Inform the cursor that this id is being invalidated. More...

void	save () final
	Prepares for state changes in underlying data in a way that allows the cursor's current position to be restored. More...

bool	restore () final
	Recovers from potential state changes in underlying data. More...

void	detachFromOperationContext () final
	Detaches from the OperationContext and releases any storage-engine state. More...

void	reattachToOperationContext (OperationContext *opCtx) final
	Reattaches to the OperationContext and reacquires any storage-engine state. More...

Public Member Functions inherited from mongo::RecordCursor
virtual	~RecordCursor ()=default

virtual std::unique_ptr< RecordFetcher >	fetcherForNext () const
	Returns a RecordFetcher if needed for a call to next() or none if unneeded. More...

Private Types
enum	Stage { FORWARD_SCAN = 0, BACKWARD_SCAN = 1, DONE = 2 }

Private Member Functions
void	advance ()

bool	_advanceToNextValidExtent ()
	Based on the direction of scan, finds the next valid (un-corrupted) extent in the chain and sets _currExtent to point to that. More...

Private Attributes
OperationContext *	_opCtx

const RecordStoreV1Base *	_recordStore

DiskLoc	_currExtent

DiskLoc	_currRecord

Stage	_stage

std::set< DiskLoc >	_seenInCurrentExtent

Member Enumeration Documentation

◆ Stage

enum mongo::RecordStoreV1RepairCursor::Stage

private

Enumerator
FORWARD_SCAN
BACKWARD_SCAN
DONE

Constructor & Destructor Documentation

◆ RecordStoreV1RepairCursor()

mongo::RecordStoreV1RepairCursor::RecordStoreV1RepairCursor	(	OperationContext *	opCtx,
		const RecordStoreV1Base *	recordStore
	)

Member Function Documentation

◆ _advanceToNextValidExtent()

bool mongo::RecordStoreV1RepairCursor::_advanceToNextValidExtent ( )

private

Based on the direction of scan, finds the next valid (un-corrupted) extent in the chain and sets _currExtent to point to that.

Returns: true if valid extent was found (_currExtent will not be null) false otherwise and _currExtent will be null

◆ advance()

void mongo::RecordStoreV1RepairCursor::advance ( )

private

◆ detachFromOperationContext()

void mongo::RecordStoreV1RepairCursor::detachFromOperationContext ( )

inlinefinalvirtual

Detaches from the OperationContext and releases any storage-engine state.

It is only legal to call this when in a "saved" state. While in the "detached" state, it is only legal to call reattachToOperationContext or the destructor. It is not legal to call detachFromOperationContext() while already in the detached state.

Implements mongo::RecordCursor.

◆ invalidate()

void mongo::RecordStoreV1RepairCursor::invalidate	(	OperationContext *	opCtx,
		const RecordId &	id
	)

virtual

Inform the cursor that this id is being invalidated.

Must be called between save and restore. The opCtx is that of the operation causing the invalidation, not the opCtx using the cursor.

WARNING: Storage engines other than MMAPv1 should use the default implementation, and not depend on this being called.

Reimplemented from mongo::RecordCursor.

◆ next()

boost::optional< Record > mongo::RecordStoreV1RepairCursor::next ( )

finalvirtual

Moves forward and returns the new data or boost::none if there is no more data.

Continues returning boost::none once it reaches EOF.

Implements mongo::RecordCursor.

◆ reattachToOperationContext()

void mongo::RecordStoreV1RepairCursor::reattachToOperationContext ( OperationContext * opCtx )

inlinefinalvirtual

Reattaches to the OperationContext and reacquires any storage-engine state.

It is only legal to call this in the "detached" state. On return, the cursor is left in a "saved" state, so callers must still call restoreState to use this object.

Implements mongo::RecordCursor.

◆ restore()

bool mongo::RecordStoreV1RepairCursor::restore ( )

inlinefinalvirtual

Recovers from potential state changes in underlying data.

Returns false if it is invalid to continue using this iterator. This usually means that capped deletes have caught up to the position of this iterator and continuing could result in missed data.

If the former position no longer exists, but it is safe to continue iterating, the following call to next() will return the next closest position in the direction of the scan, if any.

This handles restoring after either save() or SeekableRecordCursor::saveUnpositioned().

Implements mongo::RecordCursor.

◆ save()

void mongo::RecordStoreV1RepairCursor::save ( )

inlinefinalvirtual

Prepares for state changes in underlying data in a way that allows the cursor's current position to be restored.

It is safe to call save multiple times in a row. No other method (excluding destructor) may be called until successfully restored.

Implements mongo::RecordCursor.

Member Data Documentation

◆ _currExtent

DiskLoc mongo::RecordStoreV1RepairCursor::_currExtent

private

◆ _currRecord

DiskLoc mongo::RecordStoreV1RepairCursor::_currRecord

private

◆ _opCtx

OperationContext* mongo::RecordStoreV1RepairCursor::_opCtx

private

◆ _recordStore

const RecordStoreV1Base* mongo::RecordStoreV1RepairCursor::_recordStore

private

◆ _seenInCurrentExtent

std::set<DiskLoc> mongo::RecordStoreV1RepairCursor::_seenInCurrentExtent

private

◆ _stage

Stage mongo::RecordStoreV1RepairCursor::_stage

private

The documentation for this class was generated from the following files:

/home/louis/git/mongodbsource.github.io/src/src/mongo/db/storage/mmap_v1/record_store_v1_repair_iterator.h
/home/louis/git/mongodbsource.github.io/src/src/mongo/db/storage/mmap_v1/record_store_v1_repair_iterator.cpp

Detailed Description

Public Member Functions

Private Types

Private Member Functions

Private Attributes

Member Enumeration Documentation

◆ Stage

Constructor & Destructor Documentation

◆ RecordStoreV1RepairCursor()

Member Function Documentation

◆ _advanceToNextValidExtent()

◆ advance()

◆ detachFromOperationContext()

◆ invalidate()

◆ next()

◆ reattachToOperationContext()

◆ restore()

◆ save()

Member Data Documentation

◆ _currExtent

◆ _currRecord

◆ _opCtx

◆ _recordStore

◆ _seenInCurrentExtent

◆ _stage