Struct kismet_cache::sharded::Cache

pub struct Cache { /* fields omitted */ }

A sharded cache is a hash-sharded directory of cache subdirectories. Each subdirectory is managed as an independent second chance cache directory.

Implementations

impl Cache

pub fn new(base_dir: PathBuf, num_shards: usize, total_capacity: usize) -> Cache

Returns a new cache for approximately total_capacity files, stores in num_shards subdirectories of base_dir.

pub fn get(&self, key: Key<'_>) -> Result<Option<File>>

Returns a read-only file for key in the shard cache directory if it exists, or None if there is no such file. Fails with ErrorKind::InvalidInput if key.name is invalid (empty, or starts with a dot or a forward or back slash).

Implicitly “touches” the cached file if it exists.

pub fn temp_dir(&self, key: Option<Key<'_>>) -> Result<Cow<'_, Path>>

Returns a temporary directory suitable for temporary files that will be published to the shard cache directory.

When this temporary file will be published at a known Key, populate key for improved behaviour.

pub fn set(&self, key: Key<'_>, value: &Path) -> Result<()>

Inserts or overwrites the file at value as key in the sharded cache directory. There may be two entries for the same key with concurrent set or put calls. Fails with ErrorKind::InvalidInput if key.name is invalid (empty, or starts with a dot or a forward or back slash).

Always consumes the file at value on success; may consume it on error.

pub fn put(&self, key: Key<'_>, value: &Path) -> Result<()>

Inserts the file at value as key in the cache directory if there is no such cached entry already, or touches the cached file if it already exists. There may be two entries for the same key with concurrent set or put calls. Fails with ErrorKind::InvalidInput if key.name is invalid (empty, or starts with a dot or a forward or back slash).

Always consumes the file at value on success; may consume it on error.

pub fn touch(&self, key: Key<'_>) -> Result<bool>

Marks the cached file key as newly used, if it exists. Fails with ErrorKind::InvalidInput if key.name is invalid (empty, or starts with a dot or a forward or back slash).

Returns whether a file for key exists in the cache.

Trait Implementations

impl Clone for Cache

fn clone(&self) -> Cache

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Cache

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

Formats the value using the given formatter.