Remove superfluous null-checks before strdup/free

NULL checks were removed for following free functions:

- g_free "If mem is NULL it simply returns"
  https://developer.gnome.org/glib/stable/glib-Memory-Allocation.html#g-free

- g_slist_free(_full)? "NULL is considered to be the empty list"
  https://developer.gnome.org/glib/stable/glib-Singly-Linked-Lists.html

- g_strfreev "If str_array is NULL, this function simply returns."
  https://developer.gnome.org/glib/stable/glib-String-Utility-Functions.html#g-strfreev

- g_slice_free "If mem is NULL, this macro does nothing."
  https://developer.gnome.org/glib/stable/glib-Memory-Slices.html#g-slice-free

- g_match_info_free "not NULL... otherwise does nothing"
  https://developer.gnome.org/glib/stable/glib-Perl-compatible-regular-expressions.html#g-match-info-free

- dfilter_free defined in Wireshark code. Returns early when passed NULL
  epan/dfilter/dfilter.c

They were also removed around calls to g_strdup where applicable:

- g_strdup "If str is NULL it returns NULL."
  https://developer.gnome.org/glib/stable/glib-String-Utility-Functions.html#g-strdup

Change-Id: Ie80c2db89bef531edc3aed7b7c9f654e1d654d04
Reviewed-on: https://code.wireshark.org/review/23406
Petri-Dish: Roland Knall <rknall@gmail.com>
Tested-by: Petri Dish Buildbot <buildbot-no-reply@wireshark.org>
Reviewed-by: João Valverde <j@v6e.pt>

1 files changed, 2 insertions, 5 deletions

diff --git a/epan/dissectors/packet-dcerpc.c b/epan/dissectors/packet-dcerpc.c
index 4d715dae99..d958bbcc9e 100644
--- a/epan/dissectors/packet-dcerpc.c
+++ b/epan/dissectors/packet-dcerpc.c
@@ -1128,8 +1128,7 @@ dcerpc_fragment_free_temporary_key(gpointer ptr)
 {
     dcerpc_fragment_key *key = (dcerpc_fragment_key *)ptr;
 
-    if (key)
-        g_slice_free(dcerpc_fragment_key, key);
+    g_slice_free(dcerpc_fragment_key, key);
 }
 
 static void
@@ -3118,9 +3117,7 @@ dissect_deferred_pointers(packet_info *pinfo, tvbuff_t *tvb, int offset, dcerpc_
     } while (found_new_pointer);
     DISSECTOR_ASSERT(original_depth == current_depth);
 
-    if (ndr_pointer_list) {
-        g_slist_free_full(ndr_pointer_list, g_free);
-    }
+    g_slist_free_full(ndr_pointer_list, g_free);
     ndr_pointer_list = (GSList *)g_slist_nth_data(list_ndr_pointer_list, current_depth);
     len_ndr_pointer_list = g_slist_length(ndr_pointer_list);