Struct ExecutionScope

pub struct ExecutionScope { /* private fields */ }

An execution scope that is hosting tasks for a group of connections. See the module level documentation for details.

Actual execution will be delegated to an “upstream” executor - something that implements [futures::task::Spawn]. In a sense, this is somewhat of an analog of a multithreaded capable [futures::stream::FuturesUnordered], but this some additional functionality specific to the vfs library.

Use ExecutionScope::new() or ExecutionScope::build() to construct new ExecutionScopees.

Implementations

impl ExecutionScope

pub fn new() -> ExecutionScope

Constructs an execution scope. Use ExecutionScope::build() if you want to specify parameters.

pub fn build() -> ExecutionScopeParams

Constructs a new execution scope builder, wrapping the specified executor and optionally accepting additional parameters. Run ExecutionScopeParams::new() to get an actual ExecutionScope object.

pub fn active_count(&self) -> usize

Returns the active count: the number of tasks that are active and will prevent shutdown.

pub fn spawn( &self, task: impl Future<Output = ()> + Send + 'static, ) -> JoinHandle<()>

Sends a task to be executed in this execution scope. This is very similar to [futures::task::Spawn::spawn_obj()] with a minor difference that self reference is not exclusive.

If the task needs to prevent itself from being shutdown, then it should use the try_active_guard function below.

For the “vfs” library it is more convenient that this method allows non-exclusive access. And as the implementation is employing internal mutability there are no downsides. This way ExecutionScope can actually also implement [futures::task::Spawn] - it just was not necessary for now.

pub fn token_registry(&self) -> &TokenRegistry

pub fn shutdown(&self)

pub fn force_shutdown(&self)

Forcibly shut down the executor without respecting the active guards.

pub fn resurrect(&self)

Restores the executor so that it is no longer in the shut-down state. Any tasks that are still running will continue to run after calling this.

pub async fn wait(&self)

Wait for all tasks to complete.

pub fn try_active_guard(&self) -> Option<ActiveGuard>

Prevents the executor from shutting down whilst the guard is held. Returns None if the executor is shutting down.

pub fn active_guard(&self) -> ActiveGuard

As above, but succeeds even if the executor is shutting down. This can be used in drop implementations to spawn tasks that must run before the executor shuts down.

Trait Implementations

impl Clone for ExecutionScope

fn clone(&self) -> ExecutionScope

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for ExecutionScope

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

Formats the value using the given formatter.

impl PartialEq for ExecutionScope

fn eq(&self, other: &ExecutionScope) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Eq for ExecutionScope