1 files changed, 73 insertions, 0 deletions
diff --git a/third_party/rust/objc/src/rc/strong.rs b/third_party/rust/objc/src/rc/strong.rs
new file mode 100644
index 0000000000..a61881b6ff
--- /dev/null
+++ b/third_party/rust/objc/src/rc/strong.rs
@@ -0,0 +1,73 @@
+use std::fmt;
+use std::mem;
+use std::ops::Deref;
+
+use runtime::{Object, self};
+use super::WeakPtr;
+
+/// A pointer that strongly references an object, ensuring it won't be deallocated.
+pub struct StrongPtr(*mut Object);
+
+impl StrongPtr {
+    /// Constructs a `StrongPtr` to a newly created object that already has a
+    /// +1 retain count. This will not retain the object.
+    /// When dropped, the object will be released.
+    /// Unsafe because the caller must ensure the given object pointer is valid.
+    pub unsafe fn new(ptr: *mut Object) -> Self {
+        StrongPtr(ptr)
+    }
+
+    /// Retains the given object and constructs a `StrongPtr` to it.
+    /// When dropped, the object will be released.
+    /// Unsafe because the caller must ensure the given object pointer is valid.
+    pub unsafe fn retain(ptr: *mut Object) -> Self {
+        StrongPtr(runtime::objc_retain(ptr))
+    }
+
+    /// Autoreleases self, meaning that the object is not immediately released,
+    /// but will be when the autorelease pool is drained. A pointer to the
+    /// object is returned, but its validity is no longer ensured.
+    pub fn autorelease(self) -> *mut Object {
+        let ptr = self.0;
+        mem::forget(self);
+        unsafe {
+            runtime::objc_autorelease(ptr);
+        }
+        ptr
+    }
+
+    /// Returns a `WeakPtr` to self.
+    pub fn weak(&self) -> WeakPtr {
+        unsafe { WeakPtr::new(self.0) }
+    }
+}
+
+impl Drop for StrongPtr {
+    fn drop(&mut self) {
+        unsafe {
+            runtime::objc_release(self.0);
+        }
+    }
+}
+
+impl Clone for StrongPtr {
+    fn clone(&self) -> StrongPtr {
+        unsafe {
+            StrongPtr::retain(self.0)
+        }
+    }
+}
+
+impl Deref for StrongPtr {
+    type Target = *mut Object;
+
+    fn deref(&self) -> &*mut Object {
+        &self.0
+    }
+}
+
+impl fmt::Pointer for StrongPtr {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        fmt::Pointer::fmt(&self.0, f)
+    }
+}