python: 实现sha1小工具

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 %*