Re: [PATCH 1/3] Add a kstrtobool function matching semantics of existing in kernel equivalents.

[Jonathan Cameron <jic23@cam.ac.uk>]

On 03/23/11 16:23, Greg KH wrote:
> On Wed, Mar 23, 2011 at 04:15:51PM +0000, Jonathan Cameron wrote:
>> On 03/23/11 16:01, Greg KH wrote:
>>> On Wed, Mar 23, 2011 at 05:30:11PM +0200, Alexey Dobriyan wrote:
>>>> On Wed, Mar 23, 2011 at 3:39 PM, Jonathan Cameron <jic23@cam.ac.uk> wrote:
>>>>> +int kstrtobool(const char *s, bool *res)
>>>>> +{
>>>>> +       switch (s[0]) {
>>>>> +       case 'y':
>>>>> +       case 'Y':
>>>>> +       case '1':
>>>>> +               *res = true;
>>>>> +       case 'n':
>>>>> +       case 'N':
>>>>> +       case '0':
>>>>> +               *res = false;
>>>>> +       default:
>>>>> +               return -EINVAL;
>>>>> +       }
>>>>> +       return 0;
>>>>> +}
>>>>
>>>> sigh... such simple thing and so many bugs
>> Yeah, not by best work.
>>>>
>>>> The only values such function should accept is 0 and 1.
>>>
>>> Why?  That's not the way the existing kernel functions that use this
>>> work.
>>>
>>>> Have you read the rest of kstrto*() code?
>>>> Where is newline check?
>> There are plenty of nastier cases that get through than a newline
>> in the middle of the string (ybobsyouruncle -> 1 nyes->0 :)
>>>>
>>>> Anyway, I think it's better do not exist.
>>>
>>> I think it is, as it's already duplicated in at least 2 different places
>>> in the kernel, and probably more.  Once we get this implementation
>>> working correctly, we don't need to rewrite it again.
>> Perhaps naming it like this is a bad idea.  It manages to imply that it
>> has the same level of strict checking which is seen in the other kstrto*
>> functions - which is self evidently not true!
> 
> Ok, perhaps the name might need to be changed a bit, but the idea is
> still good to have.  Please try again.
> 
Any thoughts on what naming would work?  Nothing immediately comes to mind
which is why I ended up pinching the kstrto* naming...

reallysloppy_strtobool?
guessintent_strtobool?

or the old classic underscore prefix to 'encourage' people to check what it does
before using it

__strtobool?