Re: [PATCH] wrap long help lines, take two

[Michal Marek <mmarek@suse.cz>]

On 15.12.2009 07:46, Vadim Bendebury (вб) wrote:
> Tested by running
> 
> mkdir ../build/powerpc
> ARCH=powerpc make menuconfig O=../build/powerpc

Did you test this exact patch? :) I'm getting
  HOSTCC  scripts/kconfig/zconf.tab.o
In file included from scripts/kconfig/zconf.tab.c:2452:
/home/mmarek/linux-2.6/scripts/kconfig/expr.c: In function
‘expr_print_gstr_helper’:
/home/mmarek/linux-2.6/scripts/kconfig/expr.c:1103: warning: implicit
declaration of function ‘getmaxx’
/home/mmarek/linux-2.6/scripts/kconfig/expr.c:1103: error: ‘stdscr’
undeclared (first use in this function)
/home/mmarek/linux-2.6/scripts/kconfig/expr.c:1103: error: (Each
undeclared identifier is reported only once
/home/mmarek/linux-2.6/scripts/kconfig/expr.c:1103: error: for each
function it appears in.)
make[2]: *** [scripts/kconfig/zconf.tab.o] Error 1

Anyway, it's better than the last version, but see comments below.

> diff --git a/scripts/kconfig/expr.c b/scripts/kconfig/expr.c
> index 2aa49e8..203eb6d 100644
> --- a/scripts/kconfig/expr.c
> +++ b/scripts/kconfig/expr.c
> @@ -1099,9 +1099,25 @@ void expr_fprint(struct expr *e, FILE *out)
> 
>  static void expr_print_gstr_helper(void *data, struct symbol *sym,
> const char *str)
>  {
> -       str_append((struct gstr*)data, str);
> +       struct gstr *gs = (struct gstr*)data;
> +       unsigned extra_length = strlen(str) + (sym ? 4 : 0);
> +       const char *last_cr = strrchr(gs->s, '\n');
> +       unsigned screen_width = getmaxx(stdscr) - 10;
> +       unsigned last_line_length;
> +
> +       if (!last_cr) {
> +               last_cr = gs->s;
> +       }
> +
> +       last_line_length = strlen(gs->s) - (last_cr - gs->s);

You can avoid recomputing all this if you store the state in a struct
that gets passed as the data argument:

struct somename {
  struct gstr *gstr;
  int width;
  /* other bookkeeping stuff like last_line_length */
}

Then expr_gstr_print would just initialize an instance of this structure
and pass it to expr_print as the callback argument. Also, computing the
desired width should be done in mconf and passed to expr_gstr_print as
an argument. First, the other config programs (conf, qconf and gconf)
should not depend on ncurses (they can pass a zero, meaning no
wrapping), second the getmaxx(stdscr) - 10 logic really belongs to
mconf. If we make use of this feature in nconf, then there the right
number be getmaxx(stdscr) - 12 or whatever, depending on the exact layout.

Michal

> +
> +       if ((last_line_length + extra_length) > screen_width) {
> +               str_append(gs, "\\\n");
> +       }
> +
> +       str_append(gs, str);
>         if (sym)
> -               str_printf((struct gstr*)data, " [=%s]",
> sym_get_string_value(sym));
> +               str_printf(gs, " [=%s]", sym_get_string_value(sym));
>  }
> 
>  void expr_gstr_print(struct expr *e, struct gstr *gs)
> --
> 1.5.4.3