Re: [PATCH v3 2/5] rust: rbtree: add `RBTreeIterator`

[Benno Lossin]

On 25.04.24 23:45, Benno Lossin wrote:
> On 18.04.24 16:15, Matt Gilbride wrote:
>> @@ -373,6 +416,56 @@ fn drop(&mut self) {
>>       }
>>   }
>>
>> +impl<'a, K, V> IntoIterator for &'a RBTree<K, V> {
>> +    type Item = (&'a K, &'a V);
>> +    type IntoIter = RBTreeIterator<'a, K, V>;
>> +
>> +    fn into_iter(self) -> Self::IntoIter {
>> +        self.iter()
>> +    }
>> +}
>> +
>> +/// An iterator over the nodes of a [`RBTree`].
>> +///
>> +/// Instances are created by calling [`RBTree::iter`].
>> +///
>> +/// # Invariants
>> +/// - `self.next` is a valid pointer.
>> +/// - `self.next` points to a node stored inside of a valid `RBTree`.
>> +pub struct RBTreeIterator<'a, K, V> {
>> +    _tree: PhantomData<&'a RBTree<K, V>>,
>> +    next: *mut bindings::rb_node,
>> +}
>> +
>> +// SAFETY: The [`RBTreeIterator`] gives out immutable references to K and V, so it has the same
>> +// thread safety requirements as immutable references.
>> +unsafe impl<'a, K: Sync, V: Sync> Send for RBTreeIterator<'a, K, V> {}
> 
> The bounds on `K` and `V` look like typos to me. They should be `Send`
> instead.

Oops, scratch this comment, what you wrote is correct, since we treat
`RBTreeIterator` as `(&K, &V)`.

-- 
Cheers,
Benno