qubit_retry/executor/
attempt_cancel_token.rs

1/*******************************************************************************
2 *
3 *    Copyright (c) 2025 - 2026 Haixing Hu.
4 *
5 *    SPDX-License-Identifier: Apache-2.0
6 *
7 *    Licensed under the Apache License, Version 2.0.
8 *
9 ******************************************************************************/
10//! Cooperative cancellation token for blocking attempts.
11//!
12
13use std::sync::Arc;
14use std::sync::atomic::{
15    AtomicBool,
16    Ordering,
17};
18
19/// Cooperative cancellation token passed to blocking timeout attempts.
20///
21/// The retry executor marks the token as cancelled when
22/// [`crate::Retry::run_in_worker`] stops waiting for a timed-out worker thread.
23/// The worker must check [`AttemptCancelToken::is_cancelled`] and return on its
24/// own; Rust threads cannot be safely killed by the executor.
25#[derive(Debug, Clone, Default)]
26pub struct AttemptCancelToken {
27    /// Shared cancellation flag.
28    cancelled: Arc<AtomicBool>,
29}
30
31impl AttemptCancelToken {
32    /// Creates a fresh non-cancelled token.
33    ///
34    /// # Returns
35    /// A token whose cancellation flag is initially `false`.
36    #[inline]
37    pub fn new() -> Self {
38        Self::default()
39    }
40
41    /// Marks this token as cancelled.
42    ///
43    /// # Parameters
44    /// This method has no parameters.
45    ///
46    /// # Side Effects
47    /// Sets the shared cancellation flag. Clones of this token observe the same
48    /// flag.
49    #[inline]
50    pub fn cancel(&self) {
51        self.cancelled.store(true, Ordering::SeqCst);
52    }
53
54    /// Returns whether cancellation has been requested.
55    ///
56    /// # Returns
57    /// `true` after the executor or another holder calls
58    /// [`AttemptCancelToken::cancel`].
59    #[inline]
60    pub fn is_cancelled(&self) -> bool {
61        self.cancelled.load(Ordering::SeqCst)
62    }
63}
qubit_retry/executor/attempt_cancel_token.rs

qubit_retry/executor/
attempt_cancel_token.rs
