MINOR: actions: Add a function pointer to release args used by actions

Arguments used by actions are never released during HAProxy deinit. Now, it is
possible to specify a function to do so. ".release_ptr" field in the act_rule
structure may be set during the configuration parsing to a specific deinit
function depending on the action type.

include/types/action.h

@@ -108,6 +108,7 @@ struct act_rule {
 	enum act_return (*action_ptr)(struct act_rule *rule, struct proxy *px,  /* ptr to custom action */
 	                              struct session *sess, struct stream *s, int flags);
 	int (*check_ptr)(struct act_rule *rule, struct proxy *px, char **err); /* ptr to check function */
+	void (*release_ptr)(struct act_rule *rule); /* ptr to release function */
 	struct action_kw *kw;
 	struct applet applet;                  /* used for the applet registration. */
 	union {

src/haproxy.c

@@ -2293,6 +2293,8 @@ static void deinit_act_rules(struct list *rules)
 	list_for_each_entry_safe(rule, ruleb, rules, list) {
 		LIST_DEL(&rule->list);
 		deinit_acl_cond(rule->cond);
+		if (rule->release_ptr)
+			rule->release_ptr(rule);
 		free(rule);
 	}
 }