Struct zebra_state::service::finalized_state::disk_format::upgrade::DbFormatChangeThreadHandle

pub struct DbFormatChangeThreadHandle {
    update_task: Option<Arc<JoinHandle<Result<(), CancelFormatChange>>>>,
    cancel_handle: SyncSender<CancelFormatChange>,
}

A handle to a spawned format change thread.

Cloning this struct creates an additional handle to the same thread.

Concurrency

Cancelling the thread on drop has a race condition, because two handles can be dropped at the same time.

If cancelling the thread is required for correct operation or usability, the owner of the handle must call force_cancel().

Fields

update_task: Option<Arc<JoinHandle<Result<(), CancelFormatChange>>>>

A handle to the format change/check thread. If configured, this thread continues running so it can perform periodic format checks.

Panics from this thread are propagated into Zebra’s state service. The task returns an error if the upgrade was cancelled by a shutdown.

cancel_handle: SyncSender<CancelFormatChange>

A channel that tells the running format thread to finish early.

Implementations

impl DbFormatChangeThreadHandle

pub fn cancel_if_needed(&self) -> bool

Cancel the running format change thread, if this is the last handle. Returns true if it was actually cancelled.

pub fn force_cancel(&self)

Force the running format change thread to cancel, even if there are other handles.

pub fn check_for_panics(&mut self)

Check for panics in the code running in the spawned thread. If the thread exited with a panic, resume that panic.

This method should be called regularly, so that panics are detected as soon as possible.

pub fn wait_for_panics(&mut self)

Wait for the spawned thread to finish. If it exited with a panic, resume that panic.

Exits early if the thread has other outstanding handles.

This method should be called during shutdown.

Trait Implementations

impl Clone for DbFormatChangeThreadHandle

fn clone(&self) -> DbFormatChangeThreadHandle

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for DbFormatChangeThreadHandle

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

Formats the value using the given formatter.

impl Drop for DbFormatChangeThreadHandle

fn drop(&mut self)

Executes the destructor for this type.