Python :check大文件或者文件夹中所有文件MD5值

hashlib.md5

from hashlib import md5
import time
import os

def calMD5(str):     #check string的MD5值
m = md5()
m.update(str)
return m.hexdigest()

def calMD5ForFile(file):         #check文件的MD5值
statinfo = os.stat(file)
if int(statinfo.st_size)/(1024*1024) >= 1000 :
print ("File size > 1000, move to big file...")
return calMD5ForBigFile(file)
m = md5()
f = open(file, 'rb')
m.update(f.read())
f.close()
return m.hexdigest()

def calMD5ForFolder(dir,MD5File):     #check文件夹的MD5值
outfile = open(MD5File,'w')
for root, subdirs, files in os.walk(dir):
for file in files:
filefullpath = os.path.join(root, file)
"""print filefullpath"""
filerelpath = os.path.relpath(filefullpath, dir)
md5 = calMD5ForFile(filefullpath)
print(md5)
outfile.write(filerelpath+"\t\t******-----------******\t\t"+md5+"\n")
outfile.close()

def calMD5ForBigFile(file):    #check大文件的MD5值
m = md5()
f = open(file, 'rb')
buffer = 8192    # why is 8192 | 8192 is fast than 2048
while 1:
chunk = f.read(buffer)
if not chunk : break
m.update(chunk)
f.close()
return m.hexdigest()

checkmd5 = calMD5ForFolder(r'D:\software',r'C:\Users\Desktop\a.txt')
print(checkmd5)