python: 实现sha1小工具

File1: sha1.py

File2: sha1.bat

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File1: sha1.py

import hashlib
import os,sys

def CalcSha1(filepath):
    with open(filepath,‘rb‘) as f:
        sha1obj = hashlib.sha1();
        print ‘>‘,
        while(True):
            data = f.read(20971520)  #20M
            print ‘.‘,
            if (data == ‘‘):
                break
            sha1obj.update(data)
        hash = sha1obj.hexdigest()
        print ‘ END‘
        return hash.upper()

if __name__ == "__main__":
    if len(sys.argv)!=2 :
        print("Usage: \n\tsha1 filename ")
        exit(1)

    hashfile = sys.argv[1]
    if not os.path.exists(hashfile):
        hashfile = os.path.join(os.path.dirname(__file__),hashfile)
        if not os.path.exists(hashfile):
            print("cannot found file")
            exit(1)

    sha1 = CalcSha1(hashfile)
    print ‘SHA1: ‘, sha1

File2: sha1.bat

@python %~dp0sha1.py %*