Re: Build 0.6 version fail on musl libc

[Jens Axboe <axboe@kernel.dk>]

On 4/28/20 1:29 PM, Milan P. Stanić wrote:
> Hello,
> 
> I'm liburing Alpine Linux maintainer
> (https://git.alpinelinux.org/aports/tree/testing/liburing)
> 
> I tried to upgrade to 0.6 from 0.5 version but I got errors:
> include/liburing/compat.h:6:2: error: unknown type name 'int64_t'
> and
> include/liburing.h:196:17: error: unknown type name 'loff_t'; did you mean 'off_t'?
> 
> musl libc have /usr/include/fcntl.h in which loff_t is defined with:
> #define loff_t off_t
> and I tried to include it in include/liburing.h but this didn't helped.
> 
> After this I created this patch:
> ------
> --- a/src/include/liburing.h	2020-04-13 18:50:21.000000000 +0200
> +++ b/src/include/liburing.h	2020-04-23 21:43:15.923487287 +0200
> @@ -193,8 +193,8 @@
>  }
>  
>  static inline void io_uring_prep_splice(struct io_uring_sqe *sqe,
> -					int fd_in, loff_t off_in,
> -					int fd_out, loff_t off_out,
> +					int fd_in, off_t off_in,
> +					int fd_out, off_t off_out,
>  					unsigned int nbytes,
>  					unsigned int splice_flags)
>  {
> ------
> with which version 0.6 builds fine but I suspect this is not proper fix.
> 
> Could you, please, give me advice what will be proper fix these changes?

Not sure what the best fix is there, for 32-bit, your change will truncate
the offset to 32-bit as off_t is only 4 bytes there. At least that's the
case for me, maybe musl is different if it just has a nasty define for
them.

Maybe best to just make them uint64_t or something like that.

-- 
Jens Axboe