Clear the filter expression list in prefs.c.

Move filter_expression_nuke from ui/gtk to epan and rename it to
filter_expression_free. Call it in prefs_reset along with the other
preference reset routines.

This keeps the Qt filter toolbar from filling up with duplicate
expressions when the profile changes.

Change-Id: I9fae9a7b48944079ea342a126979d9e79af0d22b
Reviewed-on: https://code.wireshark.org/review/7281
Petri-Dish: Gerald Combs <gerald@wireshark.org>
Tested-by: Petri Dish Buildbot <buildbot-no-reply@wireshark.org>
Reviewed-by: Gerald Combs <gerald@wireshark.org>

debian/libwireshark0.symbols

@@ -499,6 +499,7 @@ libwireshark.so.0 libwireshark0 #MINVER#
  fc_fc4_val@Base 1.9.1
  fetch_tapped_data@Base 1.9.1
  filter_expression_new@Base 1.9.1
+ filter_expression_free@Base 1.99.3
  find_and_mark_frame_depended_upon@Base 1.12.0~rc1
  find_circuit@Base 1.9.1
  find_color_conversation_filter@Base 1.99.2

epan/filter_expressions.c

@@ -76,6 +76,18 @@ filter_expression_init(gboolean enable_prefs)
 		prefs.filter_expressions = pfilter_expression_head;
 }
 
+void
+filter_expression_free(struct filter_expression *list_head)
+{
+    if (list_head == NULL)
+        return;
+    filter_expression_free(list_head->next);
+    g_free(list_head->label);
+    g_free(list_head->expression);
+}
+
+
+
 /*
  * Editor modelines  -  http://www.wireshark.org/tools/modelines.html
  *

epan/filter_expressions.h

@@ -29,6 +29,10 @@
 extern "C" {
 #endif /* __cplusplus */
 
+/** @file
+ * Filter expressions.
+ */
+
 struct filter_expression {
 	gpointer button;	/* Filter toolbar */
 	gchar	*label;
@@ -43,12 +47,25 @@ struct filter_expression {
 
 WS_DLL_PUBLIC struct filter_expression **pfilter_expression_head;
 
+/** Create a filter expression
+ *
+ * @param label Label (button) text for the expression.
+ * @param expr The display filter for the expression.
+ * @param enabled Determines if the expression is shown in the UI.
+ * @return A newly allocated and initialized struct filter_expression.
+ */
 WS_DLL_PUBLIC
 struct filter_expression *filter_expression_new(const gchar *label,
     const gchar *expr, const gboolean enabled);
 
 void filter_expression_init(gboolean prefs);
 
+/** Clear the filter expression list.
+ * Frees each item in the list. Caller should set list_head to NULL afterward.
+ */
+WS_DLL_PUBLIC
+void filter_expression_free(struct filter_expression *list_head);
+
 #ifdef __cplusplus
 }
 #endif /* __cplusplus */

epan/prefs.c

@@ -3124,6 +3124,13 @@ prefs_reset(void)
      */
     oids_cleanup();
 
+    /*
+     * Free the filter expression list.
+     */
+
+    filter_expression_free(*pfilter_expression_head);
+    *pfilter_expression_head = NULL;
+
     /*
      * Reset the non-dissector preferences.
      */

ui/gtk/filter_expression_save_dlg.c

@@ -87,16 +87,6 @@ filter_expression_save_dlg_init(gpointer filter_tb, gpointer filter_te)
 	}
 }
 
-static void
-filter_expression_nuke(struct filter_expression *fe)
-{
-	if (fe == NULL)
-		return;
-	filter_expression_nuke(fe->next);
-	g_free(fe->label);
-	g_free(fe->expression);
-}
-
 void
 filter_expression_reinit(int what)
 {
@@ -113,7 +103,7 @@ filter_expression_reinit(int what)
 		}
 	}
 	if (what == FILTER_EXPRESSION_REINIT_DESTROY) {
-		filter_expression_nuke(*pfilter_expression_head);
+		filter_expression_free(*pfilter_expression_head);
 		*pfilter_expression_head = NULL;
 		return;
 	}
@@ -146,7 +136,7 @@ filter_expression_reinit(int what)
 			filter_expression_new(fe->label, fe->expression,
 			    fe->enabled);
 		}
-		filter_expression_nuke(prevhead);
+		filter_expression_free(prevhead);
 
 		/* Create the buttons again */
 		fe = *pfilter_expression_head;

ui/gtk/main.c

@@ -3798,7 +3798,6 @@ void change_configuration_profile (const gchar *profile_name)
     /* Set profile name and update the status bar */
     set_profile_name (profile_name);
     profile_bar_update ();
-    filter_expression_reinit(FILTER_EXPRESSION_REINIT_DESTROY);
 
     /* Reset current preferences and apply the new */
     prefs_reset();