SN-3638 已核对来源，附原文与上下文。
它不是严格意义上的即插即用替代品。我想把接口稍微清理一下。只需要改几处。
It's not an exact drop-in replacement. I wanted to clean up the interface a little. It only requires a few changes.
ScanHash_ 函数不会消失。顺带一提，这个接口的参数设计就是参照那组函数（midstate, data, hash1）镜像的。
ScanHash_ functions aren't going away. BTW, the interface of this is designed to mirror the parameters of that (midstate, data, hash1).
