Struct Resource 

pub struct Resource<D: DriverIo> { /* private fields */ }

Generic storage resource parameterized by backend driver.

Owns the common state machine (range tracking, committed/failed flags, condvar wait coordination, cancellation) and delegates backend-specific I/O to D.

Use via type aliases:

• MmapResource = Resource<MmapDriver>
• MemResource = Resource<MemDriver>

Implementations

impl<D: Driver> Resource<D>

pub fn open(cancel: CancellationToken, opts: D::Options) -> StorageResult<Self>

Open a resource from driver options with no availability observer.

D is resolved at the call site by the type of opts (e.g. Resource::open(token, MmapOptions { .. }) resolves to Resource<MmapDriver>::open). The crate-private Driver trait drives the binding without exposing its Options associated type as a second canonical path to the public MemOptions / MmapOptions.

Errors

Returns error if D::open(opts) fails (e.g. file I/O failure).

pub fn open_with_observer( cancel: CancellationToken, opts: D::Options, observer: Option<Arc<dyn AvailabilityObserver>>, ) -> StorageResult<Self>

Open a resource with an optional AvailabilityObserver. The observer (if any) fires after every successful write_at and after a successful commit that supplies a final length. Hooks run after the state lock is released.

Errors

Returns error if D::open(opts) fails.

impl Resource<MemDriver>

pub fn new(cancel: CancellationToken) -> Self

Create a new empty in-memory resource.

Panics

Panics if MemDriver::open fails (should never happen with default options).

Trait Implementations

impl<D: DriverIo> Clone for Resource<D>

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<D: DriverIo + Debug> Debug for Resource<D>

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

Formats the value using the given formatter.

impl From<Resource<MemDriver>> for StorageResource

fn from(r: MemResource) -> Self

Converts to this type from the input type.

impl From<Resource<MmapDriver>> for StorageResource

Available on non-WebAssembly only.

fn from(r: MmapResource) -> Self

Converts to this type from the input type.

impl<D: DriverIo> ResourceExt for Resource<D>

fn commit(&self, final_len: Option<u64>) -> StorageResult<()>

Mark the resource as fully written.

fn contains_range(&self, range: Range<u64>) -> bool

Check if the given byte range is fully covered by available data (non-blocking).

fn fail(&self, reason: String)

Mark the resource as failed.

fn len(&self) -> Option<u64>

Get the committed length, if known.

fn next_gap(&self, from: u64, limit: u64) -> Option<Range<u64>>

Find the first gap in available data starting from from, up to limit.

fn path(&self) -> Option<&Path>

Get the file path, if backed by a file.

fn reactivate(&self) -> StorageResult<()>

Reactivate a committed resource for continued writing.

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

Read data at the given offset into buf.

fn status(&self) -> ResourceStatus

Get resource status.

fn wait_range(&self, range: Range<u64>) -> StorageResult<WaitOutcome>

Wait until the given byte range is available.

fn write_at(&self, offset: u64, data: &[u8]) -> StorageResult<()>

Write data at the given offset.

fn is_empty(&self) -> bool

Returns true if the resource has been committed with zero length.

fn read_into(&self, buf: &mut Vec<u8>) -> StorageResult<usize>

Read the entire resource contents into a caller-provided buffer.

fn write_all(&self, data: &[u8]) -> StorageResult<()>

Write entire contents and commit atomically.