Struct VirtualDisk 

pub struct VirtualDisk { /* private fields */ }

A crashable virtual disk with two-stage durability and fault knobs.

Implementations

impl VirtualDisk

pub fn new() -> Self

An empty disk with no faults armed.

pub fn set_write_failures(&mut self, enabled: bool)

Fails every write while enabled is true.

pub fn set_fsync_failures(&mut self, enabled: bool)

Fails every fsync while enabled is true.

pub fn fail_next_write(&mut self)

Fails only the next write.

pub fn fail_next_fsync(&mut self)

Fails only the next fsync.

pub fn set_torn_write_limit(&mut self, limit: Option<usize>)

Truncates every write to at most limit bytes (a torn write). None disables truncation.

pub fn append(&mut self, path: &str, bytes: &[u8]) -> Result<usize, DiskError>

Appends bytes to the pending stage. Returns the number of bytes accepted, which a torn write may shorten. The bytes are not durable until VirtualDisk::fsync.

pub fn fsync(&mut self, path: &str) -> Result<(), DiskError>

Moves all pending bytes of path to the durable stage.

pub fn read(&self, path: &str) -> Vec<u8>

Live view: durable bytes followed by not-yet-fsynced bytes.

pub fn read_durable(&self, path: &str) -> Vec<u8>

Crash-recovery view: exactly the fsynced prefix.

pub fn durable_len(&self, path: &str) -> usize

Number of fsynced bytes for path.

pub fn pending_len(&self, path: &str) -> usize

Number of written-but-not-fsynced bytes for path.

pub fn crash(&mut self)

Simulates power loss: every pending (un-fsynced) byte is lost, on every file.

Trait Implementations

impl Debug for VirtualDisk

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

Formats the value using the given formatter.

impl Default for VirtualDisk

fn default() -> VirtualDisk

Returns the “default value” for a type.