Sebastian Thielrefactor21745135 years agoHistory
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//! Utilities to cause interruptions in common traits, like Read/Write and Iterator.use std::{    io,    sync::atomic::{AtomicBool, Ordering},}; /// A wrapper for an inner iterator which will check for interruptions on each iteration.pub struct Iter<'a, I, EFN> {    /// The actual iterator to yield elements from.    pub inner: I,    make_err: Option<EFN>,    should_interrupt: &'a AtomicBool,    is_done: bool,} impl<'a, I, EFN, E> Iter<'a, I, EFN>where    I: Iterator,    EFN: FnOnce() -> E,{    /// Create a new iterator over `inner` which checks for interruptions on each iteration and cals `make_err()` to    /// signal an interruption happened, causing no further items to be iterated from that point on.    pub fn new(inner: I, make_err: EFN, should_interrupt: &'a AtomicBool) -> Self {        Iter {            inner,            make_err: Some(make_err),            should_interrupt,            is_done: false,        }    }} impl<'a, I, EFN, E> Iterator for Iter<'a, I, EFN>where    I: Iterator,    EFN: FnOnce() -> E,{    type Item = Result<I::Item, E>;     fn next(&mut self) -> Option<Self::Item> {        if self.is_done {            return None;        }        if self.should_interrupt.load(Ordering::Relaxed) {            self.is_done = true;            return Some(Err(self.make_err.take().expect("no bug")()));        }        match self.inner.next() {            Some(next) => Some(Ok(next)),            None => {                self.is_done = true;                None            }        }    }} /// 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<'a, R> {    /// The actual implementor of [`std::io::Read`] to which interrupt support will be added.    pub inner: R,    /// The flag to trigger interruption    pub should_interrupt: &'a AtomicBool,} impl<'a, R> io::Read for Read<'a, R>where    R: io::Read,{    fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {        if self.should_interrupt.load(Ordering::Relaxed) {            return Err(io::ErrorKind::Interrupted.into());        }        self.inner.read(buf)    }} impl<'a, R> io::BufRead for Read<'a, 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)    }}