Enum CompleteCheckpointState 

pub enum CompleteCheckpointState {
    Start,
    ReadingHeader {
        reader: Box<StreamingLogicalLogReader>,
    },
    DriveEarlyTruncate {
        header_result: HeaderReadResult,
        checkpoint_result: CheckpointResult,
    },
    DriveCheckpoint,
    AwaitDbFileSync {
        completion: Completion,
        checkpoint_result: CheckpointResult,
    },
    RetryHeader {
        checkpoint_result: CheckpointResult,
        retried_crc: bool,
        phase: RetryHeaderPhase,
    },
    DriveFinalTruncate {
        checkpoint_result: CheckpointResult,
    },
}

Sub state machine for MvStore::maybe_complete_interrupted_checkpoint_nonblock. Tracks the sequence of IO yields needed to reconcile an interrupted MVCC checkpoint without blocking: read log header → optional early WAL truncate, or WAL→DB backfill + db_file.sync + log-header rewrite (with a single-shot CRC retry) + final WAL truncate.

Variants

Start

ReadingHeader

Reading the log header via the streaming reader.

Fields

reader: Box<StreamingLogicalLogReader>

DriveEarlyTruncate

wal_max_frame == 0 branch: driving the early wal.truncate_wal. checkpoint_result must persist across IO yields because truncate_wal/truncate_log tracks its truncate/sync progress through its wal_truncate_sent / wal_sync_sent flags; recreating it each re-entry would re-issue the truncate forever.

Fields

header_result: HeaderReadResult

checkpoint_result: CheckpointResult

DriveCheckpoint

Main path: driving wal.checkpoint(Truncate). Reached from a Valid header (reused via set_header) or a NoLog log (the Passive steady state); the fresh header is (re)written later in RetryHeader.

AwaitDbFileSync

Awaiting the db_file.sync completion after a successful backfill.

Fields

completion: Completion

checkpoint_result: CheckpointResult

RetryHeader

Retry loop: rewriting the log header + verifying CRC. retried_crc allows a single retry on torn-tail mismatch before failing closed.

Fields

checkpoint_result: CheckpointResult

retried_crc: bool

phase: RetryHeaderPhase

DriveFinalTruncate

Driving the final wal.truncate_wal.

Fields

checkpoint_result: CheckpointResult

Trait Implementations

impl Default for CompleteCheckpointState

fn default() -> CompleteCheckpointState

Returns the “default value” for a type.