Struct grin_store::types::DataFile

pub struct DataFile<T> { /* fields omitted */ }

Data file (MMR) wrapper around an append-only file.

Methods

impl<T> DataFile<T> where
    T: Readable + Writeable + Debug, 

pub fn open<P>(
    path: P,
    size_info: SizeInfo,
    version: ProtocolVersion
) -> Result<DataFile<T>> where
    P: AsRef<Path> + Debug, 

Open (or create) a file at the provided path on disk.

pub fn append(&mut self, data: &T) -> Result<u64>

Append an element to the file. Will not be written to disk until flush() is subsequently called. Alternatively discard() may be called to discard any pending changes.

pub fn read(&self, position: u64) -> Option<T>

Read an element from the file by position. Assumes we have already "shifted" the position to account for pruned data. Note: PMMR API is 1-indexed, but backend storage is 0-indexed.

Makes no assumptions about the size of the elements in bytes. Elements can be of variable size (handled internally in the append-only file impl).

pub fn rewind(&mut self, position: u64)

Rewind the backend file to the specified position.

pub fn flush(&mut self) -> Result<()>

Flush unsynced changes to the file to disk.

pub fn discard(&mut self)

Discard any unsynced changes to the file.

pub fn size(&self) -> u64

Size of the file in number of elements (not bytes).

pub fn path(&self) -> &Path

Path of the underlying file

pub fn as_temp_file(&self) -> Result<File>

Create a new tempfile containing the contents of this data file. This allows callers to see a consistent view of the data without locking the data file.

pub fn release(&mut self)

Drop underlying file handles

pub fn save_prune(&mut self, prune_pos: &[u64]) -> Result<()>

Write the file out to disk, pruning removed elements.