res_calendar: delete old calendars after reload

When "fetch_again_at_reload" is set in config, we create now
new object and thread for each reloaded calendar (with new
configuration). Old calendar should be then unlinked, so the
old thread can exit and free memory.

ASTERISK-26683

Change-Id: Ic17fba9371c5a8b26a6bc54ea4957c13a32a343e

res/res_calendar.c

@@ -406,7 +406,12 @@ static struct ast_calendar *build_calendar(struct ast_config *cfg, const char *c
 	struct ast_variable *v, *last = NULL;
 	int new_calendar = 0;
 
-	if (!(cal = find_calendar(cat))) {
+	cal = find_calendar(cat);
+	if (cal && cal->fetch_again_at_reload) {
+		/** Create new calendar, old will be removed during reload */
+		cal = unref_calendar(cal);
+	}
+	if (!cal) {
 		new_calendar = 1;
 		if (!(cal = ao2_alloc(sizeof(*cal), calendar_destructor))) {
 			ast_log(LOG_ERROR, "Could not allocate calendar structure. Stopping.\n");
@@ -483,7 +488,7 @@ static struct ast_calendar *build_calendar(struct ast_config *cfg, const char *c
 		}
 	}
 
-	if (new_calendar || cal->fetch_again_at_reload) {
+	if (new_calendar) {
 		cal->thread = AST_PTHREADT_NULL;
 		ast_cond_init(&cal->unload, NULL);
 		ao2_link(calendars, cal);