Re: [PATCH v8 4/7] rust: time: Add wrapper for fsleep function

[Alice Ryhl]

On Fri, Jan 17, 2025 at 10:01 AM FUJITA Tomonori
<fujita.tomonori@xxxxxxxxx> wrote:
>
> On Fri, 17 Jan 2025 16:53:26 +0900 (JST)
> FUJITA Tomonori <fujita.tomonori@xxxxxxxxx> wrote:
>
> > On Thu, 16 Jan 2025 10:27:02 +0100
> > Alice Ryhl <aliceryhl@xxxxxxxxxx> wrote:
> >
> >>> +/// This function can only be used in a nonatomic context.
> >>> +pub fn fsleep(delta: Delta) {
> >>> +    // The argument of fsleep is an unsigned long, 32-bit on 32-bit architectures.
> >>> +    // Considering that fsleep rounds up the duration to the nearest millisecond,
> >>> +    // set the maximum value to u32::MAX / 2 microseconds.
> >>> +    const MAX_DURATION: Delta = Delta::from_micros(u32::MAX as i64 >> 1);
> >>
> >> Hmm, is this value correct on 64-bit platforms?
> >
> > You meant that the maximum can be longer on 64-bit platforms? 2147484
> > milliseconds is long enough for fsleep's duration?
> >
> > If you prefer, I use different maximum durations for 64-bit and 32-bit
> > platforms, respectively.
>
> How about the following?
>
> const MAX_DURATION: Delta = Delta::from_micros(usize::MAX as i64 >> 1);

Why is there a maximum in the first place? Are you worried about
overflow on the C side?

Alice