[Cocci] Replacing one (specific!) type with another

[julia.lawall@lip6.fr (Julia Lawall)]

On Mon, 10 Oct 2016, Nikolaus Rath wrote:

> On Oct 10 2016, Nikolaus Rath <Nikolaus@rath.org> wrote:
> > On Oct 10 2016, Julia Lawall <julia.lawall@lip6.fr> wrote:
> >> On Sun, 9 Oct 2016, Nikolaus Rath wrote:
> >>
> >>> On Oct 08 2016, Julia Lawall <julia.lawall@lip6.fr> wrote:
> >>> >> > Write separate rules for that.  You would need one case for a local
> >>> >> > variable and one case fora parameter.  You can actually probably just drop
> >>> >> > the rule you have currently.  I would imagine something like the
> >>> >> > following:
> >>> >> >
> >>> >> > @@
> >>> >> > symbol f, se; // avoid unneeded warnings from Coccinelle
> >>> >> > @@
> >>> >> >
> >>> >> > struct fuse_session *
> >>> >> > -f
> >>> >> > +se
> >>> >> >  ;
> >>> >> > <...
> >>> >> > -f
> >>> >> > +se
> >>> >> > ...>
> >>> >> > @@
> >>> >> > identifier fn;
> >>> >> > @@
> >>> >> >
> >>> >> > fn(...,struct fuse_session *f,...) { <...
> >>
> >> Oops, the first line should be:
> >>
> >> fn(...,struct fuse_session *
> >> -f
> >> +se
> >>   ,...) { <...
> >>
> >> The rule works fine even when f is the first argument.
> >
> > Ouch, I guess I could have caught that too. Works like a charm now!
>
> I claimed success too early. There are still the following cases left:
>
>
> static void do_destroy(fuse_req_t req, fuse_ino_t nodeid, const void *inarg)
> {
> 	struct fuse_session *f = req->se;
> [....]
>
> I tried to adapt the rules myself as follows:
>
> @@
> symbol f, se;
> @@
> struct fuse_session *
> -f
> +se
> ;
> <...
> -f
> +se
> ...>
>
> @@
> symbol f, se;
> expression expr;
> @@
> struct fuse_session *
> -f
> +se
> = expr;
> <...
> -f
> +se
> ...>
>
>
> @@
> identifier fn;
> @@
> fn(...,struct fuse_session *
> -f
> +se
> ,...) { <...
> -f
> +se
> ...> }
>
>
> But this gives an error:
>
>
> Fatal error: exception Failure("meta: parse error:
>  = File "se-rename.cocci", line 14, column 7,  charpos = 79
>     around = 'f', whole content = symbol f, se;
> ")
>
>
> What am I doing wrong?

What version of Coccinelle are you using?  Before 1.0.6, it was not
possible to declare something to be a symbol more than once.  In any case,
once it is declared as a symbol, it is always a symbol.

julia