1 files changed, 60 insertions, 0 deletions
diff --git a/vendor/windows-core/src/ref.rs b/vendor/windows-core/src/ref.rs
new file mode 100644
index 00000000..fa70852c
--- /dev/null
+++ b/vendor/windows-core/src/ref.rs
@@ -0,0 +1,60 @@
+use super::*;
+use core::mem::transmute;
+
+/// A borrowed type with the same memory layout as the type itself that can be used to construct ABI-compatible function signatures.
+#[repr(transparent)]
+pub struct Ref<'a, T: Type<T>>(T::Abi, core::marker::PhantomData<&'a T>);
+
+impl<T: Type<T>> Ref<'_, T> {
+    /// Returns `true` if the argument is null.
+    pub fn is_null(&self) -> bool {
+        T::is_null(&self.0)
+    }
+
+    /// Converts the argument to a [`Result<&T>`] reference.
+    pub fn ok(&self) -> Result<&T> {
+        self.as_ref()
+            .ok_or_else(|| Error::from_hresult(imp::E_POINTER))
+    }
+
+    /// Converts the argument to a [`Option<&T>`] reference.
+    pub fn as_ref(&self) -> Option<&T> {
+        if self.is_null() {
+            None
+        } else {
+            unsafe { Some(self.assume_init_ref()) }
+        }
+    }
+
+    /// Converts the argument to a `&T` reference.
+    ///
+    /// # Panics
+    ///
+    /// Panics if the argument is null.
+    #[track_caller]
+    pub fn unwrap(&self) -> &T {
+        self.as_ref().expect("called `Ref::unwrap` on a null value")
+    }
+
+    /// Converts the argument to an [`Option<T>`] by cloning the reference.
+    pub fn cloned(&self) -> Option<T> {
+        self.as_ref().cloned()
+    }
+
+    unsafe fn assume_init_ref(&self) -> &T {
+        unsafe { T::assume_init_ref(&self.0) }
+    }
+}
+
+impl<T: Type<T>> core::ops::Deref for Ref<'_, T> {
+    type Target = T::Default;
+    fn deref(&self) -> &Self::Target {
+        unsafe { transmute(&self.0) }
+    }
+}
+
+impl<'a, T: Type<T>> From<&'a T::Default> for Ref<'a, T> {
+    fn from(from: &'a T::Default) -> Self {
+        unsafe { core::mem::transmute_copy(from) }
+    }
+}