[Cocci] "TODO: FunCall" in python match printing

[Julia Lawall]

On Fri, 6 Mar 2009, Carl-Daniel Hailfinger wrote:

> Hi,
> 
> I decided to use spatch for diagnostics on the refactored flashrom code.
> flashrom deals with direct memory accesses, so the code is literally
> sprinkled with volatile qualifiers for variables. Some of them don't
> make sense, especially assignments to variables which are not placed in
> mmapped flash ROM space.
> 
> The following semantic patch does almost what I want:
> 
> @r exists@
> expression b;
> typedef uint8_t;
> volatile uint8_t a;
> position p1;
> @@
>  a at p1 = b;
> 
> @script:python@
> p1 << r.p1;
> a << r.a;
> b << r.b;
> @@
> print "* file: %s line %s has assignment to unnecessarily volatile
> variable: %s = %s;" % (p1[0].file, p1[0].line, a, b)
> 
> 
> Original code:
> 
> volatile uint8_t tmp;
> tmp = readb(bios + 0x1823);
> tmp = readb(bios + 0x1820);
> tmp = readb(bios + 0x1822);
> tmp = readb(bios + 0x0418);
> tmp = readb(bios + 0x041B);
> tmp = readb(bios + 0x0419);
> tmp = readb(bios + 0x040A);
> 
> Generated messages:
> * file: sst28sf040.c line 44 has assignment to unnecessarily volatile
> variable: tmp = TODO: FunCall;
> * file: sst28sf040.c line 43 has assignment to unnecessarily volatile
> variable: tmp = TODO: FunCall;
> * file: sst28sf040.c line 42 has assignment to unnecessarily volatile
> variable: tmp = TODO: FunCall;
> * file: sst28sf040.c line 41 has assignment to unnecessarily volatile
> variable: tmp = TODO: FunCall;
> * file: sst28sf040.c line 40 has assignment to unnecessarily volatile
> variable: tmp = TODO: FunCall;
> * file: sst28sf040.c line 39 has assignment to unnecessarily volatile
> variable: tmp = TODO: FunCall;
> * file: sst28sf040.c line 38 has assignment to unnecessarily volatile
> variable: tmp = TODO: FunCall;
> 
> I'd prefer to print the whole line, but as long as the TODO remains, the
> current output will have to suffice. Actually, the output is good enough
> for my purposes.

Yes, the python support for printing out big terms is not very well 
developed.  I can probably make a quick fix for this case this morning.

If you use emacs, there is an API for generating code that works with the 
emacs org mode.  Here is an example:

@r@
position p;
@@

// Place our cocci code here
// using position p and perhaps later position p1.

@script:python@
p << r.p;
p1 << r.p1;
@@

cocci.print_main(p)
cocci.print_sec("Your msg here", p1)

Org mode will give you a link to the right place in the file.

> Just noticed: For some files, the above patch gives a warning:
>      (ONCE) Missing type information. Certainly a pb in annotate_typer.ml

Probably because it doesn't find a header file that contains some needed 
type information.

> For some other files, the warning is different:
> (ONCE) ast_to_flow: filter a directive

There is a #define that it is unable to do anything useful with.

julia