diff options
Diffstat (limited to 'src/mongo/db/storage/kv/kv_engine.h')
| -rw-r--r-- | src/mongo/db/storage/kv/kv_engine.h | 193 |
1 files changed, 95 insertions, 98 deletions
diff --git a/src/mongo/db/storage/kv/kv_engine.h b/src/mongo/db/storage/kv/kv_engine.h index ccc127c1abd..bf73380e4e9 100644 --- a/src/mongo/db/storage/kv/kv_engine.h +++ b/src/mongo/db/storage/kv/kv_engine.h @@ -39,103 +39,100 @@ namespace mongo { - class IndexDescriptor; - class OperationContext; - class RecordStore; - class RecoveryUnit; - class SortedDataInterface; - - class KVEngine { - public: - - virtual RecoveryUnit* newRecoveryUnit() = 0; - - // --------- - - /** - * Caller takes ownership - * Having multiple out for the same ns is a rules violation; - * Calling on a non-created ident is invalid and may crash. - */ - virtual RecordStore* getRecordStore( OperationContext* opCtx, - StringData ns, +class IndexDescriptor; +class OperationContext; +class RecordStore; +class RecoveryUnit; +class SortedDataInterface; + +class KVEngine { +public: + virtual RecoveryUnit* newRecoveryUnit() = 0; + + // --------- + + /** + * Caller takes ownership + * Having multiple out for the same ns is a rules violation; + * Calling on a non-created ident is invalid and may crash. + */ + virtual RecordStore* getRecordStore(OperationContext* opCtx, + StringData ns, + StringData ident, + const CollectionOptions& options) = 0; + + virtual SortedDataInterface* getSortedDataInterface(OperationContext* opCtx, + StringData ident, + const IndexDescriptor* desc) = 0; + + // + // The create and drop methods on KVEngine are not transactional. Transactional semantics + // are provided by the KVStorageEngine code that calls these. For example, drop will be + // called if a create is rolled back. A higher-level drop operation will only propagate to a + // drop call on the KVEngine once the WUOW commits. Therefore drops will never be rolled + // back and it is safe to immediately reclaim storage. + // + + virtual Status createRecordStore(OperationContext* opCtx, + StringData ns, + StringData ident, + const CollectionOptions& options) = 0; + + virtual Status createSortedDataInterface(OperationContext* opCtx, StringData ident, - const CollectionOptions& options ) = 0; - - virtual SortedDataInterface* getSortedDataInterface( OperationContext* opCtx, - StringData ident, - const IndexDescriptor* desc ) = 0; - - // - // The create and drop methods on KVEngine are not transactional. Transactional semantics - // are provided by the KVStorageEngine code that calls these. For example, drop will be - // called if a create is rolled back. A higher-level drop operation will only propagate to a - // drop call on the KVEngine once the WUOW commits. Therefore drops will never be rolled - // back and it is safe to immediately reclaim storage. - // - - virtual Status createRecordStore( OperationContext* opCtx, - StringData ns, - StringData ident, - const CollectionOptions& options ) = 0; - - virtual Status createSortedDataInterface( OperationContext* opCtx, - StringData ident, - const IndexDescriptor* desc ) = 0; - - virtual int64_t getIdentSize( OperationContext* opCtx, - StringData ident ) = 0; - - virtual Status repairIdent( OperationContext* opCtx, - StringData ident ) = 0; - - virtual Status dropIdent( OperationContext* opCtx, - StringData ident ) = 0; - - // optional - virtual int flushAllFiles( bool sync ) { return 0; } - - virtual bool isDurable() const = 0; - - /** - * This must not change over the lifetime of the engine. - */ - virtual bool supportsDocLocking() const = 0; - - /** - * Returns true if storage engine supports --directoryperdb. - * See: - * http://docs.mongodb.org/manual/reference/program/mongod/#cmdoption--directoryperdb - */ - virtual bool supportsDirectoryPerDB() const = 0; - - virtual Status okToRename( OperationContext* opCtx, - StringData fromNS, - StringData toNS, - StringData ident, - const RecordStore* originalRecordStore ) const { - return Status::OK(); - } - - virtual bool hasIdent(OperationContext* opCtx, StringData ident) const = 0; - - virtual std::vector<std::string> getAllIdents( OperationContext* opCtx ) const = 0; - - /** - * This method will be called before there is a clean shutdown. Storage engines should - * override this method if they have clean-up to do that is different from unclean shutdown. - * MongoDB will not call into the storage subsystem after calling this function. - * - * There is intentionally no uncleanShutdown(). - */ - virtual void cleanShutdown() = 0; - - /** - * The destructor will never be called from mongod, but may be called from tests. - * Engines may assume that this will only be called in the case of clean shutdown, even if - * cleanShutdown() hasn't been called. - */ - virtual ~KVEngine() {} - }; - + const IndexDescriptor* desc) = 0; + + virtual int64_t getIdentSize(OperationContext* opCtx, StringData ident) = 0; + + virtual Status repairIdent(OperationContext* opCtx, StringData ident) = 0; + + virtual Status dropIdent(OperationContext* opCtx, StringData ident) = 0; + + // optional + virtual int flushAllFiles(bool sync) { + return 0; + } + + virtual bool isDurable() const = 0; + + /** + * This must not change over the lifetime of the engine. + */ + virtual bool supportsDocLocking() const = 0; + + /** + * Returns true if storage engine supports --directoryperdb. + * See: + * http://docs.mongodb.org/manual/reference/program/mongod/#cmdoption--directoryperdb + */ + virtual bool supportsDirectoryPerDB() const = 0; + + virtual Status okToRename(OperationContext* opCtx, + StringData fromNS, + StringData toNS, + StringData ident, + const RecordStore* originalRecordStore) const { + return Status::OK(); + } + + virtual bool hasIdent(OperationContext* opCtx, StringData ident) const = 0; + + virtual std::vector<std::string> getAllIdents(OperationContext* opCtx) const = 0; + + /** + * This method will be called before there is a clean shutdown. Storage engines should + * override this method if they have clean-up to do that is different from unclean shutdown. + * MongoDB will not call into the storage subsystem after calling this function. + * + * There is intentionally no uncleanShutdown(). + */ + virtual void cleanShutdown() = 0; + + /** + * The destructor will never be called from mongod, but may be called from tests. + * Engines may assume that this will only be called in the case of clean shutdown, even if + * cleanShutdown() hasn't been called. + */ + virtual ~KVEngine() {} +}; } |