Ensure buffer has enough space

In the case of a Unix domain socket, the required buffer size may
in principle be up to PATH_MAX, so better to explicitly ensure that
there's enough space.

server/core/service.c

@@ -221,8 +221,12 @@ service_isvalid(SERVICE *service)
 static int
 serviceStartPort(SERVICE *service, SERV_LISTENER *port)
 {
+    const size_t ANY_IPV4_ADDRESS_LEN = 7; // strlen("0:0:0:0");
+
     int listeners = 0;
-    char config_bind[40];
+    size_t config_bind_len =
+        (port->address ? strlen(port->address) : ANY_IPV4_ADDRESS_LEN) + 1 + UINTLEN(port->port);
+    char config_bind[config_bind_len + 1]; // +1 for NULL
     GWPROTOCOL *funcs;
 
     if (service == NULL || service->router == NULL || service->router_instance == NULL)