Interface Link

crates/common/src/linked_list.rs:75–93

Defines how a type is tracked within a linked list. In order to support storing a single type within multiple lists, accessing the list pointers is decoupled from the entry type. # Safety Implementations must guarantee that `Target` types are pinned in memory. In other words, when a node is inserted, the value will not be moved as long as it is stored in the list.

/// other words, when a node is inserted, the value will not be moved as long as
/// it is stored in the list.
pub unsafe trait Link {
    /// Handle to the list entry.
    ///
    /// This is usually a pointer-ish type.
    type Handle;

    /// Node type.
    type Target;

    /// Convert the handle to a raw pointer without consuming the handle.
    #[allow(clippy::wrong_self_convention)]
    fn as_raw(handle: &Self::Handle) -> NonNull<Self::Target>;

    /// Convert the raw pointer to a handle
    unsafe fn from_raw(ptr: NonNull<Self::Target>) -> Self::Handle;

    /// Return the pointers for a node
    unsafe fn pointers(target: NonNull<Self::Target>) -> NonNull<Pointers<Self::Target>>;
}

/// Previous / next pointers.
pub struct Pointers<T> {