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use crate::cell::Cell;
pub struct Mutex {
// This platform has no threads, so we can use a Cell here.
locked: Cell<bool>,
}
pub type MovableMutex = Mutex;
unsafe impl Send for Mutex {}
unsafe impl Sync for Mutex {} // no threads on this platform
impl Mutex {
#[inline]
pub const fn new() -> Mutex {
Mutex { locked: Cell::new(false) }
}
#[inline]
pub unsafe fn lock(&self) {
assert_eq!(self.locked.replace(true), false, "cannot recursively acquire mutex");
}
#[inline]
pub unsafe fn unlock(&self) {
self.locked.set(false);
}
#[inline]
pub unsafe fn try_lock(&self) -> bool {
self.locked.replace(true) == false
}
}
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