Re: [PATCH 1/5] modpost: rename merror() to error()

[Masahiro Yamada <masahiroy@kernel.org>]

On Tue, Dec 1, 2020 at 7:34 PM Masahiro Yamada <masahiroy@kernel.org> wrote:
>
> The log function names, warn(), merror(), fatal() are inconsistent.
>
> Commit 2a11665945d5 ("kbuild: distinguish between errors and warnings
> in modpost") intentionally chose merror() to avoid the conflict with
> the library function error(). See man page of error(3).
>
> But, we are already causing the conflict with warn() because it is also
> a library function. See man page of warn(3). err() would be a problem
> for the same reason.
>
> The common technique to work around name conflicts is to use macros.
>
>     #define error __error
>     void __error(const char *fmt, ...)
>     {
>             <our own implementation>
>     }
>
>     #define warn __warn
>     void __warn(const char *fmt, ...)
>     {
>             <our own implementation>
>     }
>
> In this way, we can implement our own warn() and error(), still we can
> include <error.h> and <err.h> with no problem.
>
> And, commit 93c95e526a4e ("modpost: rework and consolidate logging
> interface") already did that.
>
> Since the log functions are all macros, we can use error() without
> causing "conflicting types" errors.
>
> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

This series, applied to linux-kbuild.


> ---
>
>  scripts/mod/modpost.c | 10 +++++-----
>  scripts/mod/modpost.h |  2 +-
>  2 files changed, 6 insertions(+), 6 deletions(-)
>
> diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c
> index f882ce0d9327..337f6ca4bda3 100644
> --- a/scripts/mod/modpost.c
> +++ b/scripts/mod/modpost.c
> @@ -403,8 +403,8 @@ static void sym_update_namespace(const char *symname, const char *namespace)
>          * actually an assertion.
>          */
>         if (!s) {
> -               merror("Could not update namespace(%s) for symbol %s\n",
> -                      namespace, symname);
> +               error("Could not update namespace(%s) for symbol %s\n",
> +                     namespace, symname);
>                 return;
>         }
>
> @@ -2226,7 +2226,7 @@ static int check_modname_len(struct module *mod)
>         else
>                 mod_name++;
>         if (strlen(mod_name) >= MODULE_NAME_LEN) {
> -               merror("module name is too long [%s.ko]\n", mod->name);
> +               error("module name is too long [%s.ko]\n", mod->name);
>                 return 1;
>         }
>
> @@ -2319,8 +2319,8 @@ static int add_versions(struct buffer *b, struct module *mod)
>                         continue;
>                 }
>                 if (strlen(s->name) >= MODULE_NAME_LEN) {
> -                       merror("too long symbol \"%s\" [%s.ko]\n",
> -                              s->name, mod->name);
> +                       error("too long symbol \"%s\" [%s.ko]\n",
> +                             s->name, mod->name);
>                         err = 1;
>                         break;
>                 }
> diff --git a/scripts/mod/modpost.h b/scripts/mod/modpost.h
> index 3aa052722233..f453504ad4df 100644
> --- a/scripts/mod/modpost.h
> +++ b/scripts/mod/modpost.h
> @@ -202,5 +202,5 @@ enum loglevel {
>  void modpost_log(enum loglevel loglevel, const char *fmt, ...);
>
>  #define warn(fmt, args...)     modpost_log(LOG_WARN, fmt, ##args)
> -#define merror(fmt, args...)   modpost_log(LOG_ERROR, fmt, ##args)
> +#define error(fmt, args...)    modpost_log(LOG_ERROR, fmt, ##args)
>  #define fatal(fmt, args...)    modpost_log(LOG_FATAL, fmt, ##args)
> --
> 2.27.0
>


-- 
Best Regards
Masahiro Yamada