common: cli_hush: Restore clear local variable support

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@weidmueller.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

diff --git a/common/cli_hush.c b/common/cli_hush.c
index 1ad7a509dfa8bea65a612affac10058302275f0a..171069f5f49b085dd4b37a42b2c848914c208aa5 100644 (file)
--- 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) {
                free(name);
                return -1;
        }
        *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;