extcap: fix parameters save in preferences file

Since g583150198b, extcap_arg structures holds a pointer to the current
preference value. So let's not update its value outside of the prefs API
otherwise the call to prefs_set_string_value() with pref_current done
afterwards will never notify the change and the updated value will not
be written in the preference file.
Moreover update ExtcapArgument::resetValue() method to have an empty
string instead of a NULL pointer. Otherwise prefs_set_string_value()
will not notify the change and save the restored default value in the
preference file either.

Change-Id: Ie70e79d471c75e25705c7654e420a7706ebc4032
Reviewed-on: https://code.wireshark.org/review/23308
Petri-Dish: Pascal Quantin <pascal.quantin@gmail.com>
Tested-by: Petri Dish Buildbot <buildbot-no-reply@wireshark.org>
Reviewed-by: Dario Lombardo <lomato@gmail.com>
Reviewed-by: Anders Broman <a.broman58@gmail.com>

1 files changed, 0 insertions, 10 deletions

diff --git a/extcap.c b/extcap.c
index 53bead8dd5..6bed5c4583 100644
--- a/extcap.c
+++ b/extcap.c
@@ -605,16 +605,6 @@ void extcap_cleanup(void)
         g_hash_table_destroy(_tool_for_ifname);
 }
 
-void extcap_pref_store(extcap_arg *arg, const char *newval)
-{
-    if (arg && arg->pref_valptr != NULL)
-    {
-        g_free(*arg->pref_valptr);
-        *arg->pref_valptr = g_strdup(newval);
-    }
-
-}
-
 /**
  * Obtains a pointer which can store a value for the given preference name.
  * The preference name that can be passed to the prefs API is stored into