Improved deregistering fields.

This improvement avoids use of deallocated memory (crash) if using a
deregistered field in display filter, color filter, custom column and
other cases when the field is used as "interesting field".

This functionality is currently used in http, imf and ldap preferences.

Also removed unused proto_registrar_n() as this does not work correctly
after deregistering fields.

Change-Id: I043e3bf7a98bd773c9801e712a012d1eab8a7f94
Reviewed-on: https://code.wireshark.org/review/5161
Reviewed-by: Stig Bjørlykke <stig@bjorlykke.org>
Tested-by: Stig Bjørlykke <stig@bjorlykke.org>

1 files changed, 33 insertions, 0 deletions

diff --git a/ui/gtk/main.c b/ui/gtk/main.c
index 187f954c51..058418d1fc 100644
--- a/ui/gtk/main.c
+++ b/ui/gtk/main.c
@@ -69,6 +69,7 @@
 #include <epan/column.h>
 #include <epan/disabled_protos.h>
 #include <epan/epan.h>
+#include <epan/proto.h>
 #include <epan/epan_dissect.h>
 #include <epan/dfilter/dfilter.h>
 #include <epan/strutil.h>
@@ -3823,6 +3824,38 @@ void change_configuration_profile (const gchar *profile_name)
     main_pane_load_window_geometry();
 }
 
+void
+main_fields_changed (void)
+{
+    /* Reload color filters */
+    color_filters_reload();
+
+    /* Syntax check filter */
+    filter_te_syntax_check_cb(main_display_filter_widget, NULL);
+    if (cfile.dfilter) {
+        /* Check if filter is still valid */
+        dfilter_t *dfp = NULL;
+        if (!dfilter_compile(cfile.dfilter, &dfp)) {
+            /* Not valid.  Enable 'Apply' button and remove dfilter. */
+            g_signal_emit_by_name(G_OBJECT(main_display_filter_widget), "changed");
+            g_free(cfile.dfilter);
+            cfile.dfilter = NULL;
+        }
+        dfilter_free(dfp);
+    }
+
+    if (have_custom_cols(&cfile.cinfo)) {
+        /* Recreate packet list according to new/changed/deleted fields */
+        packet_list_recreate();
+    } else if (cfile.state != FILE_CLOSED) {
+        /* Redissect packets if we have any */
+        redissect_packets();
+    }
+    destroy_packet_wins(); /* TODO: close windows until we can recreate */
+
+    proto_free_deregistered_fields();
+}
+
 /** redissect packets and update UI */
 void redissect_packets(void)
 {