Re: [PATCH v2 3/5] lib/cmdline: Allow get_options() to take 0 to validate the input

[Bartosz Golaszewski <bgolaszewski@xxxxxxxxxxxx>]

On Wed, Jan 20, 2021 at 10:45 PM Andy Shevchenko
<andriy.shevchenko@xxxxxxxxxxxxxxx> wrote:
>
> Allow get_options() to take 0 as a number of integers parameter to validate
> the input.
>
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
> ---
>  lib/cmdline.c       | 14 +++++++++++---
>  lib/cmdline_kunit.c | 10 +++++++++-
>  2 files changed, 20 insertions(+), 4 deletions(-)
>
> diff --git a/lib/cmdline.c b/lib/cmdline.c
> index 2a9ae2143e42..1106a8bcd63e 100644
> --- a/lib/cmdline.c
> +++ b/lib/cmdline.c
> @@ -91,6 +91,9 @@ EXPORT_SYMBOL(get_option);
>   *     full, or when no more numbers can be retrieved from the
>   *     string.
>   *
> + *     When @nints is 0, the function just validates the given @str and
> + *     returns amount of parseable integers as described below.

I'm not a native English speaker but it sounds like this should be
"returns the amount".

> + *
>   *     Returns:
>   *
>   *     The first element is filled by the amount of the collected numbers
> @@ -103,15 +106,20 @@ EXPORT_SYMBOL(get_option);
>
>  char *get_options(const char *str, int nints, int *ints)
>  {
> +       bool validate = nints == 0;

bool validate = (nints == 0) would be clearer IMO.

>         int res, i = 1;
>
> -       while (i < nints) {
> -               res = get_option((char **)&str, ints + i);
> +       while (i < nints || validate) {
> +               int *pint = validate ? ints : ints + i;
> +
> +               res = get_option((char **)&str, pint);
>                 if (res == 0)
>                         break;
>                 if (res == 3) {
> +                       int n = validate ? 0 : nints - i;
>                         int range_nums;
> -                       range_nums = get_range((char **)&str, ints + i, nints - i);
> +
> +                       range_nums = get_range((char **)&str, pint, n);
>                         if (range_nums < 0)
>                                 break;
>                         /*
> diff --git a/lib/cmdline_kunit.c b/lib/cmdline_kunit.c
> index 74da9ed61779..a6119c164b48 100644
> --- a/lib/cmdline_kunit.c
> +++ b/lib/cmdline_kunit.c
> @@ -109,15 +109,23 @@ static void cmdline_do_one_range_test(struct kunit *test, const char *in,
>  {
>         unsigned int i;
>         int r[16];
> +       int *p;
>
>  #define FMT    "in test %u"
>  #define FMT2   "expected %d numbers, got %d"
>  #define FMT3   "at %d"
>         memset(r, 0, sizeof(r));
>         get_options(in, ARRAY_SIZE(r), r);
> -       KUNIT_EXPECT_EQ_MSG(test, r[0], e[0], FMT " " FMT2, n, e[0], r[0]);
> +       KUNIT_EXPECT_EQ_MSG(test, r[0], e[0], FMT " (parsed) " FMT2, n, e[0], r[0]);
>         for (i = 1; i < ARRAY_SIZE(r); i++)
>                 KUNIT_EXPECT_EQ_MSG(test, r[i], e[i], FMT " " FMT3, n, i);
> +
> +       memset(r, 0, sizeof(r));
> +       get_options(in, 0, r);
> +       KUNIT_EXPECT_EQ_MSG(test, r[0], e[0], FMT " (validated) " FMT2, n, e[0], r[0]);
> +
> +       p = memchr_inv(&r[1], 0, sizeof(r) - sizeof(r[0]));
> +       KUNIT_EXPECT_PTR_EQ_MSG(test, p, (int *)0, FMT " out of bound " FMT3, n, p - r);
>  #undef FMT3
>  #undef FMT2
>  #undef FMT

Same as the other patch - just put the formatting strings into the messages.

Bart

> --
> 2.29.2
>