Enum Error 

pub enum Error {
    Io(Error),
    BadMeta(String),
    NotRetained {
        seq: u64,
        first: u64,
    },
    BeyondHead {
        seq: u64,
        head: u64,
    },
    Corrupt {
        path: PathBuf,
        offset: u64,
        what: &'static str,
    },
    Released(PathBuf),
    OutOfOrder {
        got: u64,
        expected: u64,
    },
    Follower,
    Unexpected(PathBuf),
    Poisoned {
        dir: PathBuf,
        cause: String,
    },
}

Errors of the log.

Variants

Io(Error)

I/O.

BadMeta(String)

A frame’s meta did not parse.

NotRetained

The requested sequence is below what the log retains.

Fields

seq: u64

What was asked for.

first: u64

The oldest sequence still on disk.

BeyondHead

The requested sequence is above the head.

Fields

seq: u64

What was asked for.

head: u64

The newest committed sequence.

Corrupt

A frame in the middle of a segment (not the tail) is corrupt.

Fields

path: PathBuf

Segment.

offset: u64

Offset of the frame.

what: &'static str

What was wrong.

Released(PathBuf)

The log’s files are RELEASED (Log::release): the data set under it is being grown and unmounted, so nothing may write until Log::reacquire.

OutOfOrder

An append was asked to start at a sequence that is not head + 1.

Fields

got: u64

The sequence offered.

expected: u64

The one the log would accept.

Follower

This log belongs to a TWIN: it holds the primary’s numbers and originates none. A local mutation on a twin is refused here, loudly, rather than stealing a sequence number from the primary.

Unexpected(PathBuf)

The segment directory holds a file the layout does not describe.

Poisoned

The log is POISONED (stinky rows 3 and 6, 2026-10-10): a frame’s fdatasync failed, or the cut of a half-written frame did. After a failed fsync the kernel may have dropped the dirty pages and the NEXT fsync succeeds without them (fsyncgate) — a frame its writer was told had failed would then be published by the next leader and applied by the twin. After a failed cut the next frame would land behind garbage. So nothing more is written: every append refuses with this until the log is reopened, which recovers from the last durable frame.

Fields

dir: PathBuf

The log’s directory.

cause: String

What failed.

Trait Implementations

impl Debug for Error

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Display for Error

fn fmt(&self, __formatter: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Error for Error

fn source(&self) -> Option<&(dyn Error + 'static)>

Returns the lower-level source of this error, if any.

fn description(&self) -> &str

👎Deprecated since 1.42.0:

use the Display impl or to_string()

fn cause(&self) -> Option<&dyn Error>

👎Deprecated since 1.33.0:

replaced by Error::source, which can support downcasting

fn provide<'a>(&'a self, request: &mut Request<'a>)

🔬This is a nightly-only experimental API. (error_generic_member_access)

Provides type-based access to context intended for error reports.

impl From<Error> for Error

fn from(source: Error) -> Self

Converts to this type from the input type.