Re: [PATCH 01/32] Add an ERR_CAST() macro to complement ERR_PTR and co. [try #2]

Randy Dunlap
2007-10-05T16:22:20Z

On Thu, 04 Oct 2007 16:56:07 +0100 David Howells wrote:

> Add an ERR_CAST() macro to complement ERR_PTR and co. for the purposes of
> casting an error entyped as one pointer type to an error of another pointer
> type whilst making it explicit as to what is going on.
>
> This provides a replacement for the ERR_PTR(PTR_ERR(p)) construct.
>
> Signed-off-by: David Howells <dhowells@redhat.com>
> ---
>
> include/linux/err.h | 12 ++++++++++++
> 1 files changed, 12 insertions(+), 0 deletions(-)
>
> diff --git a/include/linux/err.h b/include/linux/err.h
> index 1ab1d44..e810ca4 100644
> --- a/include/linux/err.h
> +++ b/include/linux/err.h
> @@ -34,6 +34,18 @@ static inline long IS_ERR(const void *ptr)
> return IS_ERR_VALUE((unsigned long)ptr);
> }
>
> +/**
> + * ERR_CAST - Explicitly cast an error-valued pointer to another pointer type
> + * ptr: The pointer to cast.

@ptr:

> + *
> + * Explicitly cast an error-valued pointer to another pointer type in such a
> + * way as to make it clear that's what's going on.
> + */
> +static inline void *ERR_CAST(const void *ptr)
> +{
> + return (void *) ptr;
> +}
> +
> #endif
>
> #endif /* _LINUX_ERR_H */

---
~Randy