On 12/6/23 12:59, Alice Ryhl wrote: > +/// Wraps the kernel's `struct cred`. > +/// > +/// # Invariants > +/// > +/// Instances of this type are always ref-counted, that is, a call to `get_cred` ensures that the > +/// allocation remains valid at least until the matching call to `put_cred`. > +#[repr(transparent)] > +pub struct Credential(pub(crate) Opaque<bindings::cred>); Why is the field `pub(crate)`? [...] > +// SAFETY: The type invariants guarantee that `Credential` is always ref-counted. > +unsafe impl AlwaysRefCounted for Credential { > + fn inc_ref(&self) { > + // SAFETY: The existence of a shared reference means that the refcount is nonzero. > + unsafe { bindings::get_cred(self.0.get()) }; > + } > + > + unsafe fn dec_ref(obj: core::ptr::NonNull<Self>) { > + // SAFETY: The safety requirements guarantee that the refcount is nonzero. Can you also justify the `cast()`? -- Cheers, Benno > + unsafe { bindings::put_cred(obj.cast().as_ptr()) }; > + } > +}