Struct ExtContext 

pub struct ExtContext<'a> { /* private fields */ }

Backend-agnostic context passed to VfsExtension::handle.

Presents the same register/acquire/unregister/cancel_guard surface regardless of whether the call arrived directly (in-process) or over a real RPC session, mirroring the existing direct/remote enum-dispatch pattern used elsewhere in this crate (e.g. AnyVfs, AnyFile).

The direct/remote backing types are intentionally private, so extension code can use this one context without depending on the crate’s wire protocol.

Implementations

impl<'a> ExtContext<'a>

pub fn native_capable(&self) -> bool

Whether the peer’s transport can carry native OS handles as out-of-band attachments (see ExtOsHandle).

Always false for direct (in-process) dispatch — there is no wire boundary to cross, so register already produces a zero-cost handle and there is nothing to gain from a native handle.

pub async fn cancel_guard<T, F>( &mut self, operation: F, ) -> Result<T, RequestCancelled>

where F: for<'b> AsyncFnOnce(&'b mut ExtContext<'b>) -> T,

Runs an operation which can observe request cancellation without dropping the handler.

On the remote path this delegates to CallContext::cancel_guard, which cooperatively signals cancellation requested by the peer. On the direct path this is a passthrough (see DirectContext).

pub fn register<T: ExtResource>(&self, value: T) -> ExtGift<T::Marker>

Registers a value in the session’s opaque-object table, returning a handle that can cross the wire (when remote) and be redeemed with acquire/unregister.

The result is an ExtGift, which belongs in a wire position that hands the peer a reference. The peer names it back with ExtGift::cite, and only the resulting ExtCite can be acquired.

Panics

In remote mode, if a different concrete type has already been registered under T::Marker on this session: a marker must name exactly one resource type, since it is the only type information that crosses the wire.

pub fn acquire<T: ExtResource>( &self, handle: ExtCite<T::Marker>, ) -> Result<ExtGuard<T>, InvalidHandle>

Resolves a citation of a handle previously returned by register.

pub fn unregister<T: ExtResource>( &self, handle: ExtCite<T::Marker>, ) -> Result<Option<T>, InvalidHandle>

Removes a handle previously returned by register, returning the stored value if this was the last reference to it.