103 lines
3.2 KiB
Python
103 lines
3.2 KiB
Python
|
#!/usr/bin/python
|
||
|
|
# Copyright (c) 2014 SUSE Linux Products GmbH
|
||
|
|
#
|
||
|
|
# Permission is hereby granted, free of charge, to any person obtaining a copy
|
||
|
|
# of this software and associated documentation files (the "Software"), to deal
|
||
|
|
# in the Software without restriction, including without limitation the rights
|
||
|
|
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
|
||
|
|
# copies of the Software, and to permit persons to whom the Software is
|
||
|
|
# furnished to do so, subject to the following conditions:
|
||
|
|
#
|
||
|
|
# The above copyright notice and this permission notice shall be included in
|
||
|
|
# all copies or substantial portions of the Software.
|
||
|
|
#
|
||
|
|
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
||
|
|
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
||
|
|
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
|
||
|
|
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
||
|
|
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
|
||
|
|
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
|
||
|
|
# SOFTWARE.
|
||
|
|
|
||
|
|
import struct
|
||
|
|
|
||
|
|
class Cpio(object):
|
||
|
|
def __init__(self, buf):
|
||
|
|
self.buf = buf
|
||
|
|
self.off = 0
|
||
|
|
|
||
|
|
def __iter__(self):
|
||
|
|
return self
|
||
|
|
|
||
|
|
def next(self):
|
||
|
|
f = CpioFile(self.off, self.buf)
|
||
|
|
if f.fin():
|
||
|
|
raise StopIteration
|
||
|
|
self.off = self.off+f.length()
|
||
|
|
return f
|
||
|
|
|
||
|
|
class CpioFile(object):
|
||
|
|
def __init__(self, off, buf):
|
||
|
|
self.off = off
|
||
|
|
self.buf = buf
|
||
|
|
|
||
|
|
if off&3:
|
||
|
|
raise Exception("invalid offset %d"% off)
|
||
|
|
|
||
|
|
fmt = "6s8s8s8s8s8s8s8s8s8s8s8s8s8s"
|
||
|
|
off = self.off + struct.calcsize(fmt)
|
||
|
|
|
||
|
|
fields = struct.unpack(fmt, buf[self.off:off])
|
||
|
|
|
||
|
|
if fields[0] != "070701":
|
||
|
|
raise Exception("invalid cpio header %s"%self.c_magic)
|
||
|
|
|
||
|
|
names = ("c_ino", "c_mode", "c_uid", "c_gid",
|
||
|
|
"c_nlink", "c_mtime", "c_filesize",
|
||
|
|
"c_devmajor", "c_devminor", "c_rdevmajor",
|
||
|
|
"c_rdevminor", "c_namesize", "c_check")
|
||
|
|
for (n, v) in zip(names, fields[1:]):
|
||
|
|
setattr(self, n, int(v, 16))
|
||
|
|
|
||
|
|
nlen = self.c_namesize - 1
|
||
|
|
self.name = struct.unpack('%ds'%nlen, buf[off:off+nlen])[0]
|
||
|
|
off = off + nlen + 1
|
||
|
|
if off&3:
|
||
|
|
off = off + 4-(off&3) # padding
|
||
|
|
self.payloadstart = off
|
||
|
|
|
||
|
|
def fin(self):
|
||
|
|
return self.name == 'TRAILER!!!'
|
||
|
|
|
||
|
|
def __str__(self):
|
||
|
|
return "[%s %d]"%(self.name, self.c_filesize)
|
||
|
|
|
||
|
|
def header(self):
|
||
|
|
return self.buf[self.payloadstart:self.payloadstart+self.c_filesize]
|
||
|
|
|
||
|
|
def length(self):
|
||
|
|
l = self.payloadstart-self.off + self.c_filesize
|
||
|
|
if self.c_filesize&3:
|
||
|
|
l = l + 4-(self.c_filesize&3)
|
||
|
|
return l
|
||
|
|
|
||
|
|
if __name__ == '__main__':
|
||
|
|
from optparse import OptionParser
|
||
|
|
|
||
|
|
parser = OptionParser()
|
||
|
|
parser.add_option("--debug", action="store_true", help="debug output")
|
||
|
|
parser.add_option("--verbose", action="store_true", help="verbose")
|
||
|
|
|
||
|
|
(options, args) = parser.parse_args()
|
||
|
|
|
||
|
|
for fn in args:
|
||
|
|
fh = open(fn, 'rb')
|
||
|
|
cpio = Cpio(fh.read())
|
||
|
|
for i in cpio:
|
||
|
|
print i
|
||
|
|
ofh = open(i.name, 'wb')
|
||
|
|
ofh.write(i.header())
|
||
|
|
ofh.close()
|
||
|
|
|
||
|
|
# vim: sw=4 et
|