mongo::MobileRecordStore::Cursor Class Reference

Inheritance diagram for mongo::MobileRecordStore::Cursor:

Public Member Functions
	Cursor (OperationContext *opCtx, const MobileRecordStore &rs, const std::string &path, const std::string &ident, bool forward)
boost::optional< Record >	next () final
	Moves forward and returns the new data or boost::none if there is no more data. More...
boost::optional< Record >	seekExact (const RecordId &id) final
	Seeks to a Record with the provided id. 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...
void	saveUnpositioned () final
	Prepares for state changes in underlying data without necessarily saving the current state. 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::SeekableRecordCursor
virtual std::unique_ptr< RecordFetcher >	fetcherForId (const RecordId &id) const
	Returns a RecordFetcher if needed to fetch the provided Record or none if unneeded. More...
Public Member Functions inherited from mongo::RecordCursor
virtual	~RecordCursor ()=default
virtual void	invalidate (OperationContext *opCtx, const RecordId &id)
	Inform the cursor that this id is being invalidated. More...
virtual std::unique_ptr< RecordFetcher >	fetcherForNext () const
	Returns a RecordFetcher if needed for a call to next() or none if unneeded. More...

Private Member Functions
void	_resetStatement ()
	Resets the prepared statement. More...

Private Attributes
OperationContext *	_opCtx
std::unique_ptr< SqliteStatement >	_stmt
bool	_eof = false
RecordId	_savedId
int64_t	_startIdNum
const bool	_isCapped
const bool	_forward

Constructor & Destructor Documentation

Cursor()

mongo::MobileRecordStore::Cursor::Cursor ( OperationContext *  opCtx, const MobileRecordStore &  rs, const std::string &  path, const std::string &  ident, bool  forward  )

inline

Member Function Documentation

_resetStatement()

void mongo::MobileRecordStore::Cursor::_resetStatement ( )

inlineprivate

Resets the prepared statement.

detachFromOperationContext()

void mongo::MobileRecordStore::Cursor::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.

next()

boost::optional<Record> mongo::MobileRecordStore::Cursor::next ( )

inlinefinalvirtual

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::MobileRecordStore::Cursor::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::MobileRecordStore::Cursor::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::MobileRecordStore::Cursor::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.

saveUnpositioned()

void mongo::MobileRecordStore::Cursor::saveUnpositioned ( )

inlinefinalvirtual

Prepares for state changes in underlying data without necessarily saving the current state.

The cursor's position when restored is unspecified. Caller is expected to seek rather than call next() following the restore.

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

Reimplemented from mongo::SeekableRecordCursor.

seekExact()

boost::optional<Record> mongo::MobileRecordStore::Cursor::seekExact ( const RecordId &  id )

inlinefinalvirtual

Seeks to a Record with the provided id.

If an exact match can't be found, boost::none will be returned and the resulting position of the cursor is unspecified.

Implements mongo::SeekableRecordCursor.

Member Data Documentation

_eof

bool mongo::MobileRecordStore::Cursor::_eof = false

private

_forward

const bool mongo::MobileRecordStore::Cursor::_forward

private

_isCapped

const bool mongo::MobileRecordStore::Cursor::_isCapped

private

_opCtx

OperationContext* mongo::MobileRecordStore::Cursor::_opCtx

private

_savedId

RecordId mongo::MobileRecordStore::Cursor::_savedId

private

_startIdNum

int64_t mongo::MobileRecordStore::Cursor::_startIdNum

private

_stmt

std::unique_ptr<SqliteStatement> mongo::MobileRecordStore::Cursor::_stmt

private

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

• /home/louis/git/mongodbsource.github.io/src/src/mongo/db/storage/mobile/mobile_record_store.cpp