Crate interrupt_ref_cell

A RefCell for sharing data with interrupt handlers or signal handlers on the same thread.

InterruptRefCell is just like RefCell, but disables interrupts during borrows.

See std::cell for a module-level description of cells.

Synchronization

This cell synchronizes the current thread with itself via a compiler_fence.

A compiler fence is sufficient for sharing a !Sync type, such as RefCell, with an interrupt handler on the same thread.

Caveats

Interrupts are disabled on a best-effort basis.

Holding a reference does not guarantee that interrupts are disabled. Dropping shared references in the wrong order might enable interrupts prematurely. Similarly, you can just enable interrupts manually while holding a reference.

Examples

use interrupt_ref_cell::{InterruptRefCell, LocalKeyExt};

thread_local! {
    static X: InterruptRefCell<Vec<i32>> = InterruptRefCell::new(Vec::new());
}

fn interrupt_handler() {
    X.with_borrow_mut(|v| v.push(1));
}

X.with_borrow(|v| {
    // Raise an interrupt
    raise_interrupt();
    assert_eq!(*v, vec![]);
});

// The interrupt handler runs

X.with_borrow(|v| assert_eq!(*v, vec![1]));

Structs

InterruptRef

Wraps a borrowed reference to a value in a InterruptRefCell box. A wrapper type for an immutably borrowed value from a InterruptRefCell<T>.

InterruptRefCell

A mutable memory location with dynamically checked borrow rules

InterruptRefMut

A wrapper type for a mutably borrowed value from a InterruptRefCell<T>.

Traits

LocalKeyExt