Struct AtomicFile 

pub struct AtomicFile { /* private fields */ }

Based on BasicAtomicFile which makes sure that updates are all-or-nothing. Performs commit asyncronously.

#Example

use atom_file::{AtomicFile,DummyFile,MemFile,Storage};
let mut af = AtomicFile::new(MemFile::new(), DummyFile::new());
af.write( 0, &[1,2,3,4] );
af.commit(4);
af.wait_complete();

Atomic file has two maps of writes. On commit, the latest batch of writes are sent to be written to underlying storage, and are also applied to the second map in the “CommitFile”. The CommitFile map is reset when all the updates to underlying storage have been applied.

Implementations

impl AtomicFile

pub fn new(stg: Box<dyn Storage>, upd: Box<dyn Storage>) -> Box<Self>

Construct AtomicFile with default limits. stg is the main underlying storage, upd is temporary storage for updates during commit.

pub fn new_with_limits( stg: Box<dyn Storage>, upd: Box<dyn Storage>, lim: &Limits, ) -> Box<Self>

Construct Atomic file with specified limits.

Trait Implementations

impl Storage for AtomicFile

fn commit(&mut self, size: u64)

Finish write transaction, size is new size of underlying storage.

fn size(&self) -> u64

Get the size of the underlying storage. Note : this is valid initially and after a commit but is not defined after write is called.

fn read(&self, start: u64, data: &mut [u8])

Read data.

fn write_data(&mut self, start: u64, data: Data, off: usize, len: usize)

Write Data slice.

fn write(&mut self, start: u64, data: &[u8])

Write byte slice to storage.

fn wait_complete(&self)

Wait until current writes are complete.

fn write_vec(&mut self, start: u64, data: Vec<u8>)

Write byte Vec.

fn write_u64(&mut self, start: u64, value: u64)

Write u64.

fn read_u64(&self, start: u64) -> u64

Read u64.

fn clone(&self) -> Box<dyn Storage>

Clone. note: provided method panics.