mid_registrar: Improve previous commit

Check the domain list for duplicates before appending a new one.

modules/mid_registrar/mid_registrar.c

@@ -231,29 +231,30 @@ int is_mid_reg_domain(const str *dom)
 static int domain_fixup(void** param)
 {
 	udomain_t* d;
+	str *dom_s = (str *)*param; /* CMD_PARAM_STATIC is always NT */
 	str_list *dom;
 
-	dom = pkg_malloc(sizeof *dom);
-	if (!dom) {
-		LM_ERR("oom\n");
-		return E_OUT_OF_MEM;
-	}
-	memset(dom, 0, sizeof *dom);
+	if (!is_mid_reg_domain(dom_s)) {
+		dom = pkg_malloc(sizeof *dom);
+		if (!dom) {
+			LM_ERR("oom\n");
+			return E_OUT_OF_MEM;
+		}
+		memset(dom, 0, sizeof *dom);
 
-	if (pkg_nt_str_dup(&dom->s, (str*)*param) < 0) {
-		pkg_free(dom);
-		return E_OUT_OF_MEM;
+		if (pkg_nt_str_dup(&dom->s, dom_s) < 0) {
+			pkg_free(dom);
+			return E_OUT_OF_MEM;
+		}
+
+		add_last(dom, mid_reg_domains);
 	}
 
-	if (ul.register_udomain(dom->s.s, &d) < 0) {
+	if (ul.register_udomain(dom_s->s, &d) < 0) {
 		LM_ERR("failed to register domain\n");
-		pkg_free(dom->s.s);
-		pkg_free(dom);
 		return E_UNSPEC;
 	}
 
-	add_last(dom, mid_reg_domains);
-
 	*param = (void*)d;
 	return 0;
 }