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| author | Michal 'vorner' Vaner <vorner@vorner.cz> | 2020-04-13 19:08:33 +0200 |
|---|---|---|
| committer | Michal 'vorner' Vaner <vorner@vorner.cz> | 2020-04-19 09:38:16 +0200 |
| commit | f4ded11b49aa24dcd8c0e114b427757b5d08dbe7 (patch) | |
| tree | 60803e603f5a5429e63def452a230d4c1844b097 /src/liballoc/sync.rs | |
| parent | 80ccddc0ed8627c0fc5e15c7526f2702ce64adb9 (diff) | |
| download | rust-f4ded11b49aa24dcd8c0e114b427757b5d08dbe7.tar.gz rust-f4ded11b49aa24dcd8c0e114b427757b5d08dbe7.zip | |
weak-into-raw: Add {Arc,Rc}::as_ptr
For consistency with Weak
Diffstat (limited to 'src/liballoc/sync.rs')
| -rw-r--r-- | src/liballoc/sync.rs | 26 |
1 files changed, 25 insertions, 1 deletions
diff --git a/src/liballoc/sync.rs b/src/liballoc/sync.rs index 203b386ba1d..54df2b60857 100644 --- a/src/liballoc/sync.rs +++ b/src/liballoc/sync.rs @@ -566,9 +566,33 @@ impl<T: ?Sized> Arc<T> { /// ``` #[stable(feature = "rc_raw", since = "1.17.0")] pub fn into_raw(this: Self) -> *const T { + let ptr = Self::as_ptr(&this); + mem::forget(this); + ptr + } + + /// Provides a raw pointer to the data. + /// + /// The counts are not affected in way and the `Arc` is not consumed. The pointer is valid for + /// as long as there are strong counts in the `Arc`. + /// + /// # Examples + /// + /// ``` + /// #![feature(weak_into_raw)] + /// + /// use std::sync::Arc; + /// + /// let x = Arc::new("hello".to_owned()); + /// let y = Arc::clone(&x); + /// let x_ptr = Arc::as_ptr(&x); + /// assert_eq!(x_ptr, Arc::as_ptr(&y)); + /// assert_eq!(unsafe { &*x_ptr }, "hello"); + /// ``` + #[unstable(feature = "weak_into_raw", issue = "60728")] + pub fn as_ptr(this: &Self) -> *const T { let ptr: *mut ArcInner<T> = NonNull::as_ptr(this.ptr); let fake_ptr = ptr as *mut T; - mem::forget(this); // SAFETY: This cannot go through Deref::deref. // Instead, we manually offset the pointer rather than manifesting a reference. |
