Re: [Vala] A problem with a vapi file

[Alexander Krivács Schrøder <alexschrod gmail com>]

On Fri, Mar 4, 2011 at 6:15 PM, Luca Dionisi <luca dionisi gmail com> wrote:
[...]
> We have a library with these sources:
>  libfoo.c   [http://pastebin.com/kDtaCR6Q]
>  libfoo.h   [http://pastebin.com/aDa3VEWt]
[...]
> Now I would like to use the library in vala with an interface like this:
>  test_foo.vala   [http://pastebin.com/qTAP9gqw]
> and I tried with the following vapi:
>  libfoo.vapi     [http://pastebin.com/bVnZU4NL]
>
> With this vapi the generated C file is the following:
>  test_foo.c      [http://pastebin.com/Lwu3JR8i]
>
> The difference with the first C file is that the variable that is used
> to carry a "Foo" object is of type foo_t*, while it should be a foo_t.
>
> What do I have to change in the vapi file to obtain a mapping more precise?

The problem is that you are using a typedef'd pointer. Is there any
reason you need to use this typedef within Vala? Since "foo_t" is just
an alias for "struct foo_st*", just set the cname for your Foo class
to "struct foo_st" instead of "foo_t". Vala will now output the
following:

void _vala_main (void) {
        struct foo_st* x;
        x = foo_new (3, 4);
        fprintf (stdout, "%d\n", foo_sum (x));
        _foo_destroy0 (x);
}

Which is just what your library expects, and I tried running this
code, and there are no compiler warnings and no errors:

$ valac --vapidir . --pkg foo -X -I. footest.vala libfoo.c
$ ./test
7

Hope that helps,
Alexander Krivács Schrøder