linux-kernel - Re: [PATCH v1 1/2] vsprintf: introduce %dE for error constants

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <87lfvg9r9z.fsf@intel.com>
Date:   Mon, 26 Aug 2019 13:04:24 +0300
From:   Jani Nikula <jani.nikula@...ux.intel.com>
To:     Andrew Morton <akpm@...ux-foundation.org>,
        Uwe Kleine-König 
        <uwe@...ine-koenig.org>
Cc:     Jonathan Corbet <corbet@....net>, linux-doc@...r.kernel.org,
        linux-kernel@...r.kernel.org, linux-gpio@...r.kernel.org,
        Linus Walleij <linus.walleij@...aro.org>,
        Bartosz Golaszewski <bgolaszewski@...libre.com>,
        Petr Mladek <pmladek@...e.com>,
        Sergey Senozhatsky <sergey.senozhatsky@...il.com>,
        Steven Rostedt <rostedt@...dmis.org>
Subject: Re: [PATCH v1 1/2] vsprintf: introduce %dE for error constants

On Mon, 26 Aug 2019, Jani Nikula <jani.nikula@...ux.intel.com> wrote:
> On Sat, 24 Aug 2019, Andrew Morton <akpm@...ux-foundation.org> wrote:
>>> --- a/lib/vsprintf.c
>>> +++ b/lib/vsprintf.c
>>> @@ -533,6 +533,192 @@ char *number(char *buf, char *end, unsigned long long num,
>>>  	return buf;
>>>  }
>>>  
>>> +#define ERRORCODE(x) { .str = #x, .err = x }
>>> +
>>> +static const struct {
>>> +	const char *str;
>>> +	int err;
>>> +} errorcodes[] = {
>>
>> It's a bit of a hack, but an array of char*'s and a separate array of
>> ushorts would save a bit of space.
>
> Or just
>
> #define ERRORCODE(x) [x] = #x
>
> static const char * const errorcodes[] = {
> 	ERRORCODE(EPERM),
>         ERRORCODE(ENOENT),
>         ...
> };
>
> Saves space, faster lookup, discovers at build time why EWOULDBLOCK
> would always show up as EAGAIN in the logs. We don't have holes to speak
> of in the error codes.

Meh, failed to notice the range ERESTARTSYS..ERECALLCONFLICT. Other than
that, it's nicer. ;)

BR,
Jani.

-- 
Jani Nikula, Intel Open Source Graphics Center