On 11/29/23 13:51, Alice Ryhl wrote:
> + /// Returns the credentials of the task that originally opened the file.
> + pub fn cred(&self) -> &Credential {
> + // This `read_volatile` is intended to correspond to a READ_ONCE call.
> + //
> + // SAFETY: The file is valid because the shared reference guarantees a nonzero refcount.
> + //
> + // TODO: Replace with `read_once` when available on the Rust side.
> + let ptr = unsafe { core::ptr::addr_of!((*self.0.get()).f_cred).read_volatile() };
> +
> + // SAFETY: The signature of this function ensures that the caller will only access the
> + // returned credential while the file is still valid, and the credential must stay valid
> + // while the file is valid.
About the last part of this safety comment, is this a guarantee from the
C side? If yes, then I would phrase it that way:
... while the file is still valid, and the C side ensures that the
credentials stay valid while the file is valid.
--
Cheers,
Benno
> + unsafe { Credential::from_ptr(ptr) }
> + }
> +
