sync: add getter for the mutex from a guard
@@ -573,6 +573,32 @@ impl<'a, T: ?Sized> MutexGuard<'a, T> {
marker: marker::PhantomData,
})
}
+
+ /// Returns a reference to the original `Mutex`.
+ ///
+ /// ```
+ /// use tokio::sync::{Mutex, MutexGuard};
+ ///
+ /// async fn unlock_and_relock<'l>(guard: MutexGuard<'l, u32>) -> MutexGuard<'l, u32> {
+ /// println!("1. contains: {:?}", *guard);
+ /// let mutex = MutexGuard::mutex(&guard);
+ /// drop(guard);
+ /// let guard = mutex.lock().await;
+ /// println!("2. contains: {:?}", *guard);
+ /// guard
+ /// }
+ /// #
+ /// # #[tokio::main]
+ /// # async fn main() {
+ /// # let mutex = Mutex::new(0u32);
+ /// # let guard = mutex.lock().await;
+ /// # unlock_and_relock(guard).await;
+ /// # }
+ /// ```
+ #[inline]
+ pub fn mutex(this: &Self) -> &'a Mutex<T> {
+ this.lock
+ }
}
impl<T: ?Sized> Drop for MutexGuard<'_, T> {
@@ -608,6 +634,35 @@ impl<T: ?Sized + fmt::Display> fmt::Display for MutexGuard<'_, T> {
// === impl OwnedMutexGuard ===
+impl<T: ?Sized> OwnedMutexGuard<T> {
+ /// Returns a reference to the original `Arc<Mutex>`.
+ ///
+ /// ```
+ /// use std::sync::Arc;
+ /// use tokio::sync::{Mutex, OwnedMutexGuard};
+ ///
+ /// async fn unlock_and_relock(guard: OwnedMutexGuard<u32>) -> OwnedMutexGuard<u32> {
+ /// println!("1. contains: {:?}", *guard);
+ /// let mutex: Arc<Mutex<u32>> = OwnedMutexGuard::mutex(&guard).clone();
+ /// drop(guard);
+ /// let guard = mutex.lock_owned().await;
+ /// println!("2. contains: {:?}", *guard);
+ /// guard
+ /// }
+ /// #
+ /// # #[tokio::main]
+ /// # async fn main() {
+ /// # let mutex = Arc::new(Mutex::new(0u32));
+ /// # let guard = mutex.lock_owned().await;
+ /// # unlock_and_relock(guard).await;
+ /// # }
+ /// ```
+ #[inline]
+ pub fn mutex(this: &Self) -> &Arc<Mutex<T>> {
+ &this.lock
+ }
+}
+
impl<T: ?Sized> Drop for OwnedMutexGuard<T> {
fn drop(&mut self) {
self.lock.s.release(1)
