hala_sync/
parking_lot.rs

1use std::ops;
2
3use crate::{maker::*, Lockable, LockableNew};
4
5/// A spin style mutex implementation without handle thread-specific data.
6pub struct SpinMutex<T> {
7    mutex: parking_lot::Mutex<T>,
8}
9
10impl<T> LockableNew for SpinMutex<T> {
11    type Value = T;
12
13    /// Creates a new mutex in an unlocked state ready for use.
14    fn new(t: T) -> Self {
15        Self {
16            mutex: parking_lot::Mutex::new(t),
17        }
18    }
19}
20
21impl<T: Default> Default for SpinMutex<T> {
22    fn default() -> Self {
23        Self::new(Default::default())
24    }
25}
26
27impl<T> Lockable for SpinMutex<T> {
28    type GuardMut<'a> = SpinMutexGuard<'a, T>
29    where
30        Self: 'a;
31
32    #[inline]
33    fn lock(&self) -> Self::GuardMut<'_> {
34        SpinMutexGuard {
35            locker: self,
36            guard: Some(self.mutex.lock()),
37        }
38    }
39
40    #[inline]
41    fn try_lock(&self) -> Option<Self::GuardMut<'_>> {
42        if let Some(guard) = self.mutex.try_lock() {
43            Some(SpinMutexGuard {
44                locker: self,
45                guard: Some(guard),
46            })
47        } else {
48            None
49        }
50    }
51
52    #[inline]
53    fn unlock(guard: Self::GuardMut<'_>) -> &Self {
54        let locker = guard.locker;
55
56        drop(guard);
57
58        locker
59    }
60}
61
62/// RAII type that handle `scope lock` semantics
63pub struct SpinMutexGuard<'a, T> {
64    /// a reference to the associated [`SpinMutex`]
65    locker: &'a SpinMutex<T>,
66    guard: Option<parking_lot::MutexGuard<'a, T>>,
67}
68
69impl<'a, T> Drop for SpinMutexGuard<'a, T> {
70    fn drop(&mut self) {
71        drop(self.guard.take())
72    }
73}
74
75impl<'a, T> ops::Deref for SpinMutexGuard<'a, T> {
76    type Target = T;
77
78    #[inline]
79    fn deref(&self) -> &Self::Target {
80        self.guard.as_deref().unwrap()
81    }
82}
83
84impl<'a, T> ops::DerefMut for SpinMutexGuard<'a, T> {
85    #[inline]
86    fn deref_mut(&mut self) -> &mut Self::Target {
87        self.guard.as_deref_mut().unwrap()
88    }
89}
90
91unsafe impl<'a, T: Send> Send for SpinMutexGuard<'a, T> {}
92
93/// Futures-aware [`SpinMutex`] type
94pub type AsyncSpinMutex<T> =
95    AsyncLockableMaker<SpinMutex<T>, SpinMutex<DefaultAsyncLockableMediator>>;
hala_sync/parking_lot.rs

hala_sync/
parking_lot.rs
