Subject: Re: bug#54846: [PATCH] gnu: linux: Escape the values of string-type kconfig options

From: Ludovic Courtès <[email-masked]>
Date: Thu, 28 Apr 2022 14:16:41 +0200

Hi antlers,

Did you have a chance to look into it?

TIA,
Ludo’.

Ludovic Courtès <[email-masked]> skribis:

> Hi,
>
> antlers <[email-masked]> skribis:
>
>>  * gnu/packages/linux.scm (config->string): add escape-string
>>
>> Handles characters within the set
>> (char-set-intersection char-set:ascii char-set:printing), removing
>> those which are known to be unsupported.
>
> [...]
>
>>  (define (config->string options)
>> +  (define (escape-string str)
>> +    "Returns STR with the escapes necessary to be read as a string-type
>> +    option's value. Handles characters within the set (char-set-intersection
>> +    char-set:ascii char-set:printing), removing those which are known to be
>> +    unsupported."
>
> Nitpick: You can turn the docstring into a comment since the docstring
> wouldn’t be accessible anyway.
>
>> +    (fold (match-lambda* (((match? fmt) str)
>> +			  (transform-string str match?
>> +					    (cut format #f fmt <>))))
>
> Please avoid tabs.
>
> ‘transform-string’ is from (texinfo string-utils), which is not imported
> here.  IMO, we’d rather avoid depending on this module since it’s really
> designed for the Texinfo machinery.
>
>> +	  str
>> +	  `((#\# "") ; No known way to escape # characters.
>> +	    (#\$ "$~a")
>> +	    ("\"\\'`" "\\~a")
>> +	    (";:()#" "\\\\~a")
>> +	    ("|" "\\\\\\~a")
>> +	    ;; No support for tabs, newlines, etc.
>> +	    (,(char-set->string (ucs-range->char-set 9 14)) ""))))
>
> I wonder if this should be implemented in terms of ‘string-fold’
> instead:
>
>   (string-concatenate-reverse
>     (string-fold (lambda (chr result)
>                    (match chr
>                      (#\# (cons "" result))
>                      ;; …
>                      (_ (cons (string chr) result))))
>                  '()
>                  str))
>
> Thoughts?
>
> Thanks,
> Ludo’.