From 90e789672f1e3140e96413e4815b354190a8d7e4 Mon Sep 17 00:00:00 2001
From: Amanieu d'Antras <amanieu@gmail.com>
Date: Sun, 28 Aug 2022 08:06:52 +0800
Subject: [PATCH] Add `ArcMutexGuard::into_arc`

This allows the contained `Arc` to be recovered after unlocking the
mutex.
---
 lock_api/src/mutex.rs | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/lock_api/src/mutex.rs b/lock_api/src/mutex.rs
index 4e1b879e..4982503b 100644
--- a/lock_api/src/mutex.rs
+++ b/lock_api/src/mutex.rs
@@ -692,6 +692,18 @@ impl<R: RawMutex, T: ?Sized> ArcMutexGuard<R, T> {
         &self.mutex
     }
 
+    /// Unlocks the mutex and returns the `Arc` that was held by the [`ArcMutexGuard`].
+    #[inline]
+    pub fn into_arc(self) -> Arc<Mutex<R, T>> {
+        // Safety: Skip our Drop impl and manually unlock the mutex.
+        let arc = unsafe { ptr::read(&self.mutex) };
+        mem::forget(self);
+        unsafe {
+            arc.raw.unlock();
+        }
+        arc
+    }
+
     /// Temporarily unlocks the mutex to execute the given function.
     ///
     /// This is safe because `&mut` guarantees that there exist no other