Create creates a WAL ready for appending records.

Exist returns true if there are any files in a given directory.

Open opens the WAL at the given snap.

OpenForRead only opens the wal files for read.

Repair tries to repair ErrUnexpectedEOF in the last wal file by truncating.

ValidSnapshotEntries returns all the valid snapshot entries in the wal logs in the given directory.

Verify reads through the given WAL and verifies that it is not corrupted.

64MB.

WAL is a logical representation of the stable storage.

HardState implement custom state data struct for save the system latest state to wal.

LogEntry implement custom entry data struct with entry index.

Snapshot implement custom snapshot struct with entry index.