Re: cocci script hints request

[Julia Lawall]

On Tue, 13 Apr 2021, Fabio Aiuto wrote:

> Hi,
>
> I would like to improve the following coccinelle script:
>
> @@
> expression a, fmt;
> expression list var_args;
> @@
>
> -       DBG_871X_LEVEL(a, fmt, var_args);
> +       printk(fmt, var_args);
>
> I would  replace the DBG_871X_LEVEL macro with printk, but
> I can't find a way to add KERN_* constant prefix to the fmt
> argument in the + code line. If i try this
>
> @@
> expression a, fmt;
> expression list var_args;
> @@
>
> -       DBG_871X_LEVEL(a, fmt, var_args);
> +       printk(KERN_DEBUG fmt, var_args);
>
> plus: parse error:
>   File "../test.cocci", line 94, column 20, charpos = 1171
>   around = 'fmt',
>   whole content = +	printk(KERN_DEBUG fmt, var_args);
>
> how could I do this?

Although I certainly agree with Greg, I'll answer the question from a
technical point of view.

I'm not sure that that kind of compound string is supported for a
metavariable.  It is possible to get around this problem using a python
script.  If you ever need to do this for a better reason, you can take a
look at demos/pythontococci.cocci in the Coccinelle source code
distribution.

julia