Re: [RESEND PATCH 1/2] tools/libxl: Mark pointer args of many functions constant

[Anthony PERARD <anthony.perard@citrix.com>]

On Fri, Dec 18, 2020 at 01:37:44PM -0800, Elliott Mitchell wrote:
> Anything *_is_empty(), *_is_default(), or *_gen_json() is going to be
> examining the pointed to thing, not modifying it.  This potentially
> results in higher-performance output.  This also allows spreading
> constants further, allowing more checking and security.
> 
> Signed-off-by: Elliott Mitchell <ehem+xen@m5p.com>
> ---
> diff --git a/tools/libs/light/libxl_internal.h b/tools/libs/light/libxl_internal.h
> index 028bc013d9..e3df881d08 100644
> --- a/tools/libs/light/libxl_internal.h
> +++ b/tools/libs/light/libxl_internal.h
[..]
> -static inline bool libxl__string_is_default(char **s)
> +static inline bool libxl__string_is_default(char *const *s)

That looks weird to not also have "char" been "const", but I've tried to
change that and the compiler wasn't cooperative so I guess that's fine.


> diff --git a/tools/libs/light/libxl_nocpuid.c b/tools/libs/light/libxl_nocpuid.c
> index f47336565b..73580351b3 100644
> --- a/tools/libs/light/libxl_nocpuid.c
> +++ b/tools/libs/light/libxl_nocpuid.c
> @@ -40,7 +40,7 @@ void libxl__cpuid_legacy(libxl_ctx *ctx, uint32_t domid, bool restore,
>  }
>  
>  yajl_gen_status libxl_cpuid_policy_list_gen_json(yajl_gen hand,
> -                                libxl_cpuid_policy_list *pcpuid)
> +                                const libxl_cpuid_policy_list *pcpuid)

That change is missing in libxl_cpuid.c.


The rest looks fine, so once libxl_cpuid.c is fix, you can have my Reviewed-by.

Thanks,

-- 
Anthony PERARD