[evolution] I#898 - Calendar: Crash on deleting event

[Milan Crha <mcrha src gnome org>]

commit 9160e7e5ee351013019dd2f692691d80ec405df3
Author: Milan Crha <mcrha redhat com>
Date:   Thu Mar 11 17:02:40 2021 +0100

    I#898 - Calendar: Crash on deleting event
    
    Closes https://gitlab.gnome.org/GNOME/evolution/-/issues/898

 src/calendar/gui/e-calendar-view.c | 43 +++++++++++++++++++++++---------------
 1 file changed, 26 insertions(+), 17 deletions(-)
---
diff --git a/src/calendar/gui/e-calendar-view.c b/src/calendar/gui/e-calendar-view.c
index e562940852..540a73f4f7 100644
--- a/src/calendar/gui/e-calendar-view.c
+++ b/src/calendar/gui/e-calendar-view.c
@@ -160,6 +160,9 @@ calendar_view_delete_event (ECalendarView *cal_view,
        ECalComponent *comp;
        ECalComponentVType vtype;
        ESourceRegistry *registry;
+       ECalClient *client;
+       ICalComponent *icalcomp;
+       time_t instance_start;
        gboolean delete = TRUE;
 
        if (!is_comp_data_valid (event))
@@ -172,12 +175,17 @@ calendar_view_delete_event (ECalendarView *cal_view,
        e_cal_component_set_icalcomponent (comp, i_cal_component_clone (event->comp_data->icalcomp));
        vtype = e_cal_component_get_vtype (comp);
 
+       /* Remember structure values, because the 'event' can be freed while the question dialog is opened */
+       instance_start = event->comp_data->instance_start;
+       client = g_object_ref (event->comp_data->client);
+       icalcomp = e_cal_component_get_icalcomponent (comp);
+
        /*FIXME remove it once the we dont set the recurrence id for all the generated instances */
-       if (!only_occurrence && !e_cal_client_check_recurrences_no_master (event->comp_data->client))
+       if (!only_occurrence && !e_cal_client_check_recurrences_no_master (client))
                e_cal_component_set_recurid (comp, NULL);
 
        /*FIXME Retract should be moved to Groupwise features plugin */
-       if (calendar_view_check_for_retract (comp, event->comp_data->client)) {
+       if (calendar_view_check_for_retract (comp, client)) {
                gchar *retract_comment = NULL;
                gboolean retract = FALSE;
 
@@ -189,7 +197,7 @@ calendar_view_delete_event (ECalendarView *cal_view,
                        icomp = e_cal_component_get_icalcomponent (comp);
                        i_cal_component_set_method (icomp, I_CAL_METHOD_CANCEL);
 
-                       e_cal_ops_send_component (model, event->comp_data->client, icomp);
+                       e_cal_ops_send_component (model, client, icomp);
                }
        } else if (e_cal_model_get_confirm_delete (model))
                delete = e_cal_dialogs_delete_component (
@@ -202,10 +210,10 @@ calendar_view_delete_event (ECalendarView *cal_view,
                rid = e_cal_component_get_recurid_as_string (comp);
 
                if (itip_has_any_attendees (comp) &&
-                   (itip_organizer_is_user (registry, comp, event->comp_data->client) ||
-                    itip_sentby_is_user (registry, comp, event->comp_data->client))
+                   (itip_organizer_is_user (registry, comp, client) ||
+                    itip_sentby_is_user (registry, comp, client))
                    && e_cal_dialogs_cancel_component ((GtkWindow *) gtk_widget_get_toplevel (GTK_WIDGET 
(cal_view)),
-                                               event->comp_data->client,
+                                               client,
                                                comp, TRUE)) {
                        if (only_occurrence && !e_cal_component_is_instance (comp)) {
                                ECalComponentRange *range;
@@ -222,7 +230,7 @@ calendar_view_delete_event (ECalendarView *cal_view,
                        }
 
                        itip_send_component_with_model (model, I_CAL_METHOD_CANCEL,
-                               comp, event->comp_data->client, NULL, NULL,
+                               comp, client, NULL, NULL,
                                NULL, E_ITIP_SEND_COMPONENT_FLAG_STRIP_ALARMS);
                }
 
@@ -235,7 +243,7 @@ calendar_view_delete_event (ECalendarView *cal_view,
 
                if (only_occurrence) {
                        if (e_cal_component_is_instance (comp)) {
-                               e_cal_ops_remove_component (model, event->comp_data->client, uid, rid, 
E_CAL_OBJ_MOD_THIS, FALSE);
+                               e_cal_ops_remove_component (model, client, uid, rid, E_CAL_OBJ_MOD_THIS, 
FALSE);
                        } else {
                                ICalTime *instance_rid;
                                ICalTimezone *zone = NULL;
@@ -246,7 +254,7 @@ calendar_view_delete_event (ECalendarView *cal_view,
                                if (dt && e_cal_component_datetime_get_tzid (dt)) {
                                        GError *local_error = NULL;
 
-                                       if (!e_cal_client_get_timezone_sync (event->comp_data->client,
+                                       if (!e_cal_client_get_timezone_sync (client,
                                                e_cal_component_datetime_get_tzid (dt), &zone, NULL, 
&local_error))
                                                zone = NULL;
 
@@ -261,24 +269,25 @@ calendar_view_delete_event (ECalendarView *cal_view,
                                e_cal_component_datetime_free (dt);
 
                                instance_rid = i_cal_time_new_from_timet_with_zone (
-                                       event->comp_data->instance_start,
+                                       instance_start,
                                        TRUE, zone ? zone : i_cal_timezone_get_utc_timezone ());
-                               e_cal_util_remove_instances_ex (event->comp_data->icalcomp, instance_rid, 
E_CAL_OBJ_MOD_THIS,
-                                       e_cal_client_tzlookup_cb, event->comp_data->client);
-                               e_cal_ops_modify_component (model, event->comp_data->client, 
event->comp_data->icalcomp,
+                               e_cal_util_remove_instances_ex (icalcomp, instance_rid, E_CAL_OBJ_MOD_THIS,
+                                       e_cal_client_tzlookup_cb, client);
+                               e_cal_ops_modify_component (model, client, icalcomp,
                                        E_CAL_OBJ_MOD_THIS, E_CAL_OPS_SEND_FLAG_DONT_SEND);
 
                                g_clear_object (&instance_rid);
                        }
-               } else if (e_cal_util_component_is_instance (event->comp_data->icalcomp) ||
-                          e_cal_util_component_has_recurrences (event->comp_data->icalcomp))
-                       e_cal_ops_remove_component (model, event->comp_data->client, uid, rid, 
E_CAL_OBJ_MOD_ALL, FALSE);
+               } else if (e_cal_util_component_is_instance (icalcomp) ||
+                          e_cal_util_component_has_recurrences (icalcomp))
+                       e_cal_ops_remove_component (model, client, uid, rid, E_CAL_OBJ_MOD_ALL, FALSE);
                else
-                       e_cal_ops_remove_component (model, event->comp_data->client, uid, NULL, 
E_CAL_OBJ_MOD_THIS, FALSE);
+                       e_cal_ops_remove_component (model, client, uid, NULL, E_CAL_OBJ_MOD_THIS, FALSE);
 
                g_free (rid);
        }
 
+       g_clear_object (&client);
        g_object_unref (comp);
 }