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#[cfg(not(feature = "std"))]
pub use no_std_lock::*;
#[cfg(feature = "std")]
pub use std_lock::*;
#[cfg(feature = "std")]
mod std_lock {
use std::sync::Mutex as StdMutex;
pub use std::sync::MutexGuard;
/// A wrapper around [`std::sync::Mutex`].
#[derive(Debug)]
pub struct Mutex<T> {
inner: StdMutex<T>,
}
impl<T> Mutex<T> {
/// Creates a new mutex in an unlocked state ready for use.
pub fn new(data: T) -> Self {
Self {
inner: StdMutex::new(data),
}
}
/// Acquires the mutex, blocking the current thread until it is able to do so.
///
/// This will return `None` in the case the mutex is poisoned.
#[inline]
pub fn lock(&self) -> Option<MutexGuard<'_, T>> {
self.inner.lock().ok()
}
}
}
#[cfg(not(feature = "std"))]
mod no_std_lock {
use alloc::boxed::Box;
use core::fmt::Debug;
use core::ops::DerefMut;
use crate::sync::Arc;
/// A no-std compatible wrapper around [`Lock`].
#[derive(Debug)]
pub struct Mutex<T> {
inner: Arc<dyn Lock<T>>,
}
impl<T: Send + 'static> Mutex<T> {
/// Creates a new mutex in an unlocked state ready for use.
pub fn new<M>(val: T) -> Self
where
M: MakeMutex,
T: Send + 'static,
{
Self {
inner: M::make_mutex(val),
}
}
/// Acquires the mutex, blocking the current thread until it is able to do so.
///
/// This will return `None` in the case the mutex is poisoned.
#[inline]
pub fn lock(&self) -> Option<MutexGuard<'_, T>> {
self.inner.lock().ok()
}
}
/// A lock protecting shared data.
pub trait Lock<T>: Debug + Send + Sync {
/// Acquire the lock.
fn lock(&self) -> Result<MutexGuard<'_, T>, Poisoned>;
}
/// A lock builder.
pub trait MakeMutex {
/// Create a new mutex.
fn make_mutex<T>(value: T) -> Arc<dyn Lock<T>>
where
T: Send + 'static;
}
/// A no-std compatible mutex guard.
pub type MutexGuard<'a, T> = Box<dyn DerefMut<Target = T> + 'a>;
/// A marker type used to indicate `Lock::lock` failed due to a poisoned lock.
pub struct Poisoned;
}