[PATCH] common: cli_hush: Restore clear local variable support

[Simon Glass]

Hi Stefan,

On Sat, 1 Apr 2023 at 03:43, Stefan Herbrechtsmeier
<stefan.herbrechtsmeier-oss at weidmueller.com> wrote:
>
> From: Stefan Herbrechtsmeier <stefan.herbrechtsmeier at weidmueller.com>
>
> The u-boot hush shell doesn’t support the unset command to clear a
> variable and therefore an empty value ("c=") should be a valid value
> for the set_local_var function to clear the variable. This partial
> reverts commit aa722529635c ("common: cli_hush: avoid dead code") and
> only checks for a `=` in the string. Additionally explicit call the
> unset_local_var function to remove the variable if the value is empty.
>
> Signed-off-by: Stefan Herbrechtsmeier <stefan.herbrechtsmeier at weidmueller.com>
>
> ---
>
>  common/cli_hush.c | 8 +++++++-
>  1 file changed, 7 insertions(+), 1 deletion(-)
>
> diff --git a/common/cli_hush.c b/common/cli_hush.c
> index 1ad7a509df..c3f7dd12a0 100644
> --- a/common/cli_hush.c
> +++ b/common/cli_hush.c
> @@ -2171,12 +2171,18 @@ int set_local_var(const char *s, int flg_export)
>          * NAME=VALUE format.  So the first order of business is to
>          * split 's' on the '=' into 'name' and 'value' */
>         value = strchr(name, '=');
> -       if (value == NULL || *(value + 1) == 0) {
> +       if (value == NULL) {

if (!value)

>                 free(name);
>                 return -1;
>         }
>         *value++ = 0;
>
> +       if (*value == 0) {

if (!*value)

> +               unset_local_var(name);
> +               free(name);
> +               return 0;
> +       }
> +
>         for(cur = top_vars; cur; cur = cur->next) {
>                 if(strcmp(cur->name, name)==0)
>                         break;
> --
> 2.30.2

I think this should have a test, e.g. in
test/py/tests/test_hush_if_test.py or perhaps a C test?

Regards,
Simon