http://blog.csdn.net/qwiwuqo/article/details/40111721
http://www.droidsec.cn/%E5%B8%B8%E8%A7%81android-native%E5%B4%A9%E6%BA%83%E5%8F%8A%E9%94%99%E8%AF%AF%E5%8E%9F%E5%9B%A0/