//! Process-global interrupt handling//!//! This module contains facilities to globally request an interrupt, which will cause supporting computations to//! abort once it is observed.//! Such checks for interrupts are provided in custom implementations of various traits to transparently add interrupt//! support to methods who wouldn't otherwise by injecting it. see [`Read`]. #[cfg(all(feature = "interrupt-handler", not(feature = "disable-interrupts")))]mod _impl {    use std::{        io,        sync::atomic::{AtomicUsize, Ordering},    };     /// Initialize a signal handler to listen to SIGINT and SIGTERM and trigger our [`trigger()`][super::trigger()] that way.    ///    /// When `Ctrl+C` is pressed, a message will be sent to `message_channel` to inform the user about it being registered, after all    /// actually responding to it is implementation dependent and might thus take some time (or not work at all)    ///    /// # Note    ///    /// This implementation is available only with the **interrupt-handler** feature toggle with the **disable-interrupts** feature disabled.    pub fn init_handler(mut message_channel: impl io::Write + Send + 'static) {        ctrlc::set_handler(move || {            const MESSAGES: &[&str] = &[                "interrupt requested",                 "please wait…",                 "the program will respond soon…",                 "if the program doesn't respond quickly enough, please let us know here: https://github.com/Byron/gitoxide/issues"            ];            static CURRENT_MESSAGE: AtomicUsize = AtomicUsize::new(0);            if !super::is_triggered() {                CURRENT_MESSAGE.store(0, Ordering::Relaxed);            }            let msg_idx = CURRENT_MESSAGE.fetch_add(1, Ordering::Relaxed);            super::IS_INTERRUPTED.store(true, Ordering::Relaxed);            writeln!(message_channel, "{}", MESSAGES[msg_idx % MESSAGES.len()]).ok();        })        .expect("it is up to the application to ensure only one interrupt handler is installed, and this function is called only once.")    }}use std::io;#[cfg(not(feature = "disable-interrupts"))]use std::sync::atomic::{AtomicBool, Ordering}; #[cfg(any(feature = "disable-interrupts", not(feature = "interrupt-handler")))]mod _impl {    use std::io;     /// Does nothing, as the **disable-interrupts** feature is enabled while the **interrupt-handler** feature is not present.    pub fn init_handler(_message_channel: impl io::Write + Send + 'static) {}}pub use _impl::init_handler; /// A wrapper for implementors of [`std::io::Read`] or [`std::io::BufRead`] with interrupt support.////// It fails a [read][`std::io::Read::read`] while an interrupt was requested.pub struct Read<R> {    /// The actual implementor of [`std::io::Read`] to which interrupt support will be added    pub inner: R,} impl<R> io::Read for Read<R>where    R: io::Read,{    fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {        if is_triggered() {            return Err(io::Error::new(io::ErrorKind::Other, "interrupted by user"));        }        self.inner.read(buf)    }} impl<R> io::BufRead for Read<R>where    R: io::BufRead,{    fn fill_buf(&mut self) -> io::Result<&[u8]> {        self.inner.fill_buf()    }     fn consume(&mut self, amt: usize) {        self.inner.consume(amt)    }} #[cfg(not(feature = "disable-interrupts"))]static IS_INTERRUPTED: AtomicBool = AtomicBool::new(false); /// Returns true if an interrupt is requested.////// Only implemented if the **disable-interrupts** feature toggle is not present.#[cfg(not(feature = "disable-interrupts"))]pub fn is_triggered() -> bool {    IS_INTERRUPTED.load(Ordering::Relaxed)} /// Returns always false if the **disable-interrupts** feature is present.#[cfg(feature = "disable-interrupts")]pub fn is_triggered() -> bool {    false} /// Trigger an interrupt, signalling to those checking for [`is_triggered()`] to stop what they are doing.////// # Note/// Only effective if the **disable-interrupts** feature is **not** present.pub fn trigger() {    #[cfg(not(feature = "disable-interrupts"))]    IS_INTERRUPTED.store(true, Ordering::Relaxed);}/// Sets the interrupt request to false, thus allowing those checking for [`is_triggered()`] to proceed.////// Call this in code that is able to trigger an interrupt./// This may also be performed by the [`ResetOnDrop`] helper to assure the trigger state is returned/// to its original state.////// # Note/// Only effective if the **disable-interrupts** feature is **not** present.pub fn reset() {    #[cfg(not(feature = "disable-interrupts"))]    IS_INTERRUPTED.store(false, Ordering::Relaxed);} /// Useful if some parts of the program set the interrupt programmatically to cause others to stop, while/// assuring the interrupt state is reset at the end of the function to avoid other side-effects.////// Note that this is inherently racy and that this will only work deterministically if there is only one/// top-level function running in a process.pub struct ResetOnDrop {    was_interrupted: bool,} impl Default for ResetOnDrop {    fn default() -> Self {        ResetOnDrop {            was_interrupted: is_triggered(),        }    }} impl Drop for ResetOnDrop {    fn drop(&mut self) {        if self.was_interrupted {            trigger()        } else {            reset()        }    }}