Struct FileSource 

pub struct FileSource { /* private fields */ }

Wrap a raw OS file as an ImageSource using positioned reads (pread/seek_read) — NOT a Mutex<Seek>, so parallel workers never serialize on one cursor at the bottom of the stack.

Implementations

impl FileSource

pub fn open(path: impl AsRef<Path>) -> VfsResult<Self>

Open path read-only as a base source.

pub fn from_file(file: File) -> VfsResult<Self>

Wrap an already-open file.

Trait Implementations

impl ImageSource for FileSource

fn len(&self) -> u64

Logical size in bytes of this stream.

fn read_at(&self, offset: u64, buf: &mut [u8]) -> VfsResult<usize>

Fill buf starting at byte offset. Returns bytes read (0 at/after EOF). Never panics; a short read past EOF returns the available prefix length.

fn is_empty(&self) -> bool

True when the stream is zero-length.

fn extents(&self) -> Extents

Allocated-extent map. Default = one dense extent covering [0, len).

fn view(&self, offset: u64, len: usize) -> Option<SourceView<'_>>

Optional zero-copy fast path. None when the backing cannot lend a contiguous view (the caller then uses ImageSource::read_at).

fn source_id(&self) -> SourceId

Stable identity for cache keying and lineage.