[m-rev.] for review: add uint64 to string conversin for bases 8 and 16

[Peter Wang]

On Sun, 13 Dec 2020 19:37:01 +1100 Julien Fischer <jfischer at opturion.com> wrote:
> 
> For review by anyone.
> 
> --------------------
> 
> Add uint64 to string conversion for bases 8 and 16.
> 
> library/string.m:
>       Add functions for converting uint64s to strings of base 8 or base 16
>       digits. For most integer types we can cast to a uint and then use the
>       uint versions of these operations but for 64-bit types we cannot since
>       on some of our supported platforms uints are 32-bit.
> 
> NEWS:
>       Announce the additions.
> 
> tests/hard_coded/Mmakefile:
> tests/hard_coded/uint64_string_conv.{m,exp}:
>       Add a test of the new functions.

> diff --git a/library/string.m b/library/string.m
> index 35519ea..c02beab 100644
> --- a/library/string.m
> +++ b/library/string.m
> @@ -5857,6 +5871,86 @@ int_to_base_string_group_2(NegN, Base, Curr, GroupLength, Sep, Str) :-
> 
>   %---------------------%
> 
> +:- pragma foreign_proc("C",
> +    uint64_to_hex_string(U64::in) = (S::uo),
> +    [will_not_call_mercury, promise_pure, thread_safe, will_not_modify_trail],
> +"
> +    char buffer[21]; // 20 for digits, 1 for nul.

Should be 17. Not that it matters particularly.

> +    sprintf(buffer, ""%"" PRIx64, U64);
> +    MR_allocate_aligned_string_msg(S, strlen(buffer), MR_ALLOC_ID);
> +    strcpy(S, buffer);
> +").

> +%---------------------%
> +
> +:- pragma foreign_proc("C",
> +    uint64_to_uc_hex_string(U64::in) = (S::uo),
> +    [will_not_call_mercury, promise_pure, thread_safe, will_not_modify_trail],
> +"
> +    char buffer[21]; // 20 for digits, 1 for nul.

Ditto.

> +    sprintf(buffer, ""%"" PRIX64, U64);
> +    MR_allocate_aligned_string_msg(S, strlen(buffer), MR_ALLOC_ID);
> +    strcpy(S, buffer);
> +").
> +

That looks fine, otherwise.

Peter