DeDRM_tools/ePub_Fixer/lib/zipfix.py
Apprentice Alf bc968f8eca tools v3.2
First appearance of combined windows python app
2015-03-05 07:25:35 +00:00

161 lines
4.8 KiB
Python

#!/usr/bin/env python
import sys
import zlib
import zipfile
import os
import os.path
import getopt
from struct import unpack
_FILENAME_LEN_OFFSET = 26
_EXTRA_LEN_OFFSET = 28
_FILENAME_OFFSET = 30
_MAX_SIZE = 64 * 1024
class fixZip:
def __init__(self, zinput, zoutput):
self.inzip = zipfile.ZipFile(zinput,'r')
self.outzip = zipfile.ZipFile(zoutput,'w')
# open the input zip for reading only as a raw file
self.bzf = file(zinput,'rb')
def getlocalname(self, zi):
local_header_offset = zi.header_offset
self.bzf.seek(local_header_offset + _FILENAME_LEN_OFFSET)
leninfo = self.bzf.read(2)
local_name_length, = unpack('<H', leninfo)
self.bzf.seek(local_header_offset + _FILENAME_OFFSET)
local_name = self.bzf.read(local_name_length)
return local_name
def uncompress(self, cmpdata):
dc = zlib.decompressobj(-15)
data = ''
while len(cmpdata) > 0:
if len(cmpdata) > _MAX_SIZE :
newdata = cmpdata[0:_MAX_SIZE]
cmpdata = cmpdata[_MAX_SIZE:]
else:
newdata = cmpdata
cmpdata = ''
newdata = dc.decompress(newdata)
unprocessed = dc.unconsumed_tail
if len(unprocessed) == 0:
newdata += dc.flush()
data += newdata
cmpdata += unprocessed
unprocessed = ''
return data
def getfiledata(self, zi):
# get file name length and exta data length to find start of file data
local_header_offset = zi.header_offset
self.bzf.seek(local_header_offset + _FILENAME_LEN_OFFSET)
leninfo = self.bzf.read(2)
local_name_length, = unpack('<H', leninfo)
self.bzf.seek(local_header_offset + _EXTRA_LEN_OFFSET)
exinfo = self.bzf.read(2)
extra_field_length, = unpack('<H', exinfo)
self.bzf.seek(local_header_offset + _FILENAME_OFFSET + local_name_length + extra_field_length)
data = None
# if not compressed we are good to go
if zi.compress_type == zipfile.ZIP_STORED:
data = self.bzf.read(zi.file_size)
# if compressed we must decompress it using zlib
if zi.compress_type == zipfile.ZIP_DEFLATED:
cmpdata = self.bzf.read(zi.compress_size)
data = self.uncompress(cmpdata)
return data
def fix(self):
# get the zipinfo for each member of the input archive
# and copy member over to output archive
# if problems exist with local vs central filename, fix them
# also fix bad epub compression
# write mimetype file first, if present, and with no compression
for zinfo in self.inzip.infolist():
if zinfo.filename == "mimetype":
nzinfo = zinfo
try:
data = self.inzip.read(zinfo.filename)
except zipfile.BadZipfile or zipfile.error:
local_name = self.getlocalname(zinfo)
data = self.getfiledata(zinfo)
nzinfo.filename = local_name
nzinfo.date_time = zinfo.date_time
nzinfo.compress_type = zipfile.ZIP_STORED
nzinfo.flag_bits = 0
nzinfo.internal_attr = 0
nzinfo.extra = ""
self.outzip.writestr(nzinfo,data)
break
# write the rest of the files
for zinfo in self.inzip.infolist():
if zinfo.filename != "mimetype":
data = None
nzinfo = zinfo
try:
data = self.inzip.read(zinfo.filename)
except zipfile.BadZipfile or zipfile.error:
local_name = self.getlocalname(zinfo)
data = self.getfiledata(zinfo)
nzinfo.filename = local_name
nzinfo.date_time = zinfo.date_time
nzinfo.compress_type = zinfo.compress_type
nzinfo.flag_bits = 0
nzinfo.internal_attr = 0
self.outzip.writestr(nzinfo,data)
self.bzf.close()
self.inzip.close()
self.outzip.close()
def usage():
print """usage: zipfix.py inputzip outputzip
inputzip is the source zipfile to fix
outputzip is the fixed zip archive
"""
def repairBook(infile, outfile):
if not os.path.exists(infile):
print "Error: Input Zip File does not exist"
return 1
try:
fr = fixZip(infile, outfile)
fr.fix()
return 0
except Exception, e:
print "Error Occurred ", e
return 2
def main(argv=sys.argv):
if len(argv)!=3:
usage()
return 1
infile = argv[1]
outfile = argv[2]
return repairBook(infile, outfile)
if __name__ == '__main__' :
sys.exit(main())