uncrustify: function definition argument indenting on separate line

Question

I have this:

char *
foo(a,b)
int a;
int b;
{
...
}

I want this:

char *
foo(a,b)
    int a;// indented 
    int b;// indented
{
...
}

The indenting works for function body code but I cannot find an option to make this style of argument (old style code being resurrected) indented.

Which directive can do this? I have tried all that seem remotely appropriate.