python-ox/oxlib/file.py
2009-06-14 21:22:47 +02:00

57 lines
1.7 KiB
Python

# -*- coding: utf-8 -*-
# vi:si:et:sw=4:sts=4:ts=4
# GPL 2008
from __future__ import division
import os
import hashlib
import sys
import struct
def sha1sum(filename):
sha1 = hashlib.sha1()
file=open(filename)
buffer=file.read(4096)
while buffer:
sha1.update(buffer)
buffer=file.read(4096)
file.close()
return sha1.hexdigest()
'''
os hash - http://trac.opensubtitles.org/projects/opensubtitles/wiki/HashSourceCodes
plus modification for files < 64k, buffer is filled with file data and padded with 0
'''
def oshash(filename):
try:
longlongformat = 'q' # long long
bytesize = struct.calcsize(longlongformat)
f = open(filename, "rb")
filesize = os.path.getsize(filename)
hash = filesize
if filesize < 65536:
for x in range(int(filesize/bytesize)):
buffer = f.read(bytesize)
(l_value,)= struct.unpack(longlongformat, buffer)
hash += l_value
hash = hash & 0xFFFFFFFFFFFFFFFF #to remain as 64bit number
else:
for x in range(int(65536/bytesize)):
buffer = f.read(bytesize)
(l_value,)= struct.unpack(longlongformat, buffer)
hash += l_value
hash = hash & 0xFFFFFFFFFFFFFFFF #to remain as 64bit number
f.seek(max(0,filesize-65536),0)
for x in range(int(65536/bytesize)):
buffer = f.read(bytesize)
(l_value,)= struct.unpack(longlongformat, buffer)
hash += l_value
hash = hash & 0xFFFFFFFFFFFFFFFF
f.close()
returnedhash = "%016x" % hash
return returnedhash
except(IOError):
return "IOError"