1 files changed, 168 insertions, 0 deletions
diff --git a/vendor/futures-util/src/stream/futures_unordered/iter.rs b/vendor/futures-util/src/stream/futures_unordered/iter.rs
new file mode 100644
index 000000000..04db5ee75
--- /dev/null
+++ b/vendor/futures-util/src/stream/futures_unordered/iter.rs
@@ -0,0 +1,168 @@
+use super::task::Task;
+use super::FuturesUnordered;
+use core::marker::PhantomData;
+use core::pin::Pin;
+use core::sync::atomic::Ordering::Relaxed;
+
+/// Mutable iterator over all futures in the unordered set.
+#[derive(Debug)]
+pub struct IterPinMut<'a, Fut> {
+    pub(super) task: *const Task<Fut>,
+    pub(super) len: usize,
+    pub(super) _marker: PhantomData<&'a mut FuturesUnordered<Fut>>,
+}
+
+/// Mutable iterator over all futures in the unordered set.
+#[derive(Debug)]
+pub struct IterMut<'a, Fut: Unpin>(pub(super) IterPinMut<'a, Fut>);
+
+/// Immutable iterator over all futures in the unordered set.
+#[derive(Debug)]
+pub struct IterPinRef<'a, Fut> {
+    pub(super) task: *const Task<Fut>,
+    pub(super) len: usize,
+    pub(super) pending_next_all: *mut Task<Fut>,
+    pub(super) _marker: PhantomData<&'a FuturesUnordered<Fut>>,
+}
+
+/// Immutable iterator over all the futures in the unordered set.
+#[derive(Debug)]
+pub struct Iter<'a, Fut: Unpin>(pub(super) IterPinRef<'a, Fut>);
+
+/// Owned iterator over all futures in the unordered set.
+#[derive(Debug)]
+pub struct IntoIter<Fut: Unpin> {
+    pub(super) len: usize,
+    pub(super) inner: FuturesUnordered<Fut>,
+}
+
+impl<Fut: Unpin> Iterator for IntoIter<Fut> {
+    type Item = Fut;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        // `head_all` can be accessed directly and we don't need to spin on
+        // `Task::next_all` since we have exclusive access to the set.
+        let task = self.inner.head_all.get_mut();
+
+        if (*task).is_null() {
+            return None;
+        }
+
+        unsafe {
+            // Moving out of the future is safe because it is `Unpin`
+            let future = (*(**task).future.get()).take().unwrap();
+
+            // Mutable access to a previously shared `FuturesUnordered` implies
+            // that the other threads already released the object before the
+            // current thread acquired it, so relaxed ordering can be used and
+            // valid `next_all` checks can be skipped.
+            let next = (**task).next_all.load(Relaxed);
+            *task = next;
+            self.len -= 1;
+            Some(future)
+        }
+    }
+
+    fn size_hint(&self) -> (usize, Option<usize>) {
+        (self.len, Some(self.len))
+    }
+}
+
+impl<Fut: Unpin> ExactSizeIterator for IntoIter<Fut> {}
+
+impl<'a, Fut> Iterator for IterPinMut<'a, Fut> {
+    type Item = Pin<&'a mut Fut>;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        if self.task.is_null() {
+            return None;
+        }
+
+        unsafe {
+            let future = (*(*self.task).future.get()).as_mut().unwrap();
+
+            // Mutable access to a previously shared `FuturesUnordered` implies
+            // that the other threads already released the object before the
+            // current thread acquired it, so relaxed ordering can be used and
+            // valid `next_all` checks can be skipped.
+            let next = (*self.task).next_all.load(Relaxed);
+            self.task = next;
+            self.len -= 1;
+            Some(Pin::new_unchecked(future))
+        }
+    }
+
+    fn size_hint(&self) -> (usize, Option<usize>) {
+        (self.len, Some(self.len))
+    }
+}
+
+impl<Fut> ExactSizeIterator for IterPinMut<'_, Fut> {}
+
+impl<'a, Fut: Unpin> Iterator for IterMut<'a, Fut> {
+    type Item = &'a mut Fut;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        self.0.next().map(Pin::get_mut)
+    }
+
+    fn size_hint(&self) -> (usize, Option<usize>) {
+        self.0.size_hint()
+    }
+}
+
+impl<Fut: Unpin> ExactSizeIterator for IterMut<'_, Fut> {}
+
+impl<'a, Fut> Iterator for IterPinRef<'a, Fut> {
+    type Item = Pin<&'a Fut>;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        if self.task.is_null() {
+            return None;
+        }
+
+        unsafe {
+            let future = (*(*self.task).future.get()).as_ref().unwrap();
+
+            // Relaxed ordering can be used since acquire ordering when
+            // `head_all` was initially read for this iterator implies acquire
+            // ordering for all previously inserted nodes (and we don't need to
+            // read `len_all` again for any other nodes).
+            let next = (*self.task).spin_next_all(self.pending_next_all, Relaxed);
+            self.task = next;
+            self.len -= 1;
+            Some(Pin::new_unchecked(future))
+        }
+    }
+
+    fn size_hint(&self) -> (usize, Option<usize>) {
+        (self.len, Some(self.len))
+    }
+}
+
+impl<Fut> ExactSizeIterator for IterPinRef<'_, Fut> {}
+
+impl<'a, Fut: Unpin> Iterator for Iter<'a, Fut> {
+    type Item = &'a Fut;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        self.0.next().map(Pin::get_ref)
+    }
+
+    fn size_hint(&self) -> (usize, Option<usize>) {
+        self.0.size_hint()
+    }
+}
+
+impl<Fut: Unpin> ExactSizeIterator for Iter<'_, Fut> {}
+
+// SAFETY: we do nothing thread-local and there is no interior mutability,
+// so the usual structural `Send`/`Sync` apply.
+unsafe impl<Fut: Send> Send for IterPinRef<'_, Fut> {}
+unsafe impl<Fut: Sync> Sync for IterPinRef<'_, Fut> {}
+
+unsafe impl<Fut: Send> Send for IterPinMut<'_, Fut> {}
+unsafe impl<Fut: Sync> Sync for IterPinMut<'_, Fut> {}
+
+unsafe impl<Fut: Send + Unpin> Send for IntoIter<Fut> {}
+unsafe impl<Fut: Sync + Unpin> Sync for IntoIter<Fut> {}