# Copyright 2023 Ant Group Co., Ltd.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#      https://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.


import hashlib

_BUF_SIZE = 64 * 1024


def sha256sum(filename: str):
    h = hashlib.sha256()
    global _BUF_SIZE
    bs = bytearray(_BUF_SIZE)
    with open(filename, 'rb') as f:
        while num := f.readinto(bs):  # noqa
            h.update(bs[:num])
    return h.hexdigest()
