Re: [musl] [PATCH] [f]statvfs: allocate spare for f_type

[Szabolcs Nagy <nsz@port70.net>]

* наб <nabijaczleweli@nabijaczleweli.xyz> [2023-06-23 22:36:11 +0200]:
> This is the only missing part in struct statvfs.
> The LSB calls [f]statfs() deprecated, and its weird types are definitely
> off-putting. However, its use is required to get f_type.
> 
> Instead, allocate one of the six spares to f_type,
> copied directly from struct statfs.
> This then becomes a small extension to the standard interface on Linux,
> instead of two different interfaces, one of which is quite odd due to
> being an ABI type, and there no longer is any reason to use statfs().
> 
> The underlying kernel type is a mess, but all architectures agree on u32
> (or more) for the ABI, and all filesystem magicks are 32-bit integers.
> 
> Link: https://lore.kernel.org/linux-man/f54kudgblgk643u32tb6at4cd3kkzha6hslahv24szs4raroaz@ogivjbfdaqtb/t/#u

fwiw this looks good to me assuming the glibc patch gets accepted:

https://patchwork.sourceware.org/project/glibc/patch/169a6ec2a9957495275964afd0697fa3aea1c6b6.1687552604.git.nabijaczleweli@nabijaczleweli.xyz/


> ---
>  include/sys/statvfs.h | 3 ++-
>  src/stat/statvfs.c    | 1 +
>  2 files changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/include/sys/statvfs.h b/include/sys/statvfs.h
> index 57a6b806..71d9d1f9 100644
> --- a/include/sys/statvfs.h
> +++ b/include/sys/statvfs.h
> @@ -23,7 +23,8 @@ struct statvfs {
>  	unsigned long f_fsid;
>  #endif
>  	unsigned long f_flag, f_namemax;
> -	int __reserved[6];
> +	unsigned int f_type;
> +	int __reserved[5];
>  };
>  
>  int statvfs (const char *__restrict, struct statvfs *__restrict);
> diff --git a/src/stat/statvfs.c b/src/stat/statvfs.c
> index bfbb5fee..bc12da8b 100644
> --- a/src/stat/statvfs.c
> +++ b/src/stat/statvfs.c
> @@ -39,6 +39,7 @@ static void fixup(struct statvfs *out, const struct statfs *in)
>  	out->f_fsid = in->f_fsid.__val[0];
>  	out->f_flag = in->f_flags;
>  	out->f_namemax = in->f_namelen;
> +	out->f_type = in->f_type;
>  }
>  
>  int statvfs(const char *restrict path, struct statvfs *restrict buf)
> -- 
> 2.39.2