python/pakfire/packages/tar.py

   1 #!/usr/bin/python
   2 ###############################################################################
   3 #                                                                             #
   4 # Pakfire - The IPFire package management system                              #
   5 # Copyright (C) 2012 Pakfire development team                                 #
   6 #                                                                             #
   7 # This program is free software: you can redistribute it and/or modify        #
   8 # it under the terms of the GNU General Public License as published by        #
   9 # the Free Software Foundation, either version 3 of the License, or           #
  10 # (at your option) any later version.                                         #
  11 #                                                                             #
  12 # This program is distributed in the hope that it will be useful,             #
  13 # but WITHOUT ANY WARRANTY; without even the implied warranty of              #
  14 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the               #
  15 # GNU General Public License for more details.                                #
  16 #                                                                             #
  17 # You should have received a copy of the GNU General Public License           #
  18 # along with this program.  If not, see <http://www.gnu.org/licenses/>.       #
  19 #                                                                             #
  20 ###############################################################################
  21
  22 import os
  23 import tarfile
  24
  25 import logging
  26 log = logging.getLogger("pakfire")
  27
  28 import pakfire.lzma as lzma
  29 import pakfire.util as util
  30 from pakfire.constants import *
  31 from pakfire.i18n import _
  32
  33 class InnerTarFile(tarfile.TarFile):
  34         def __init__(self, *args, **kwargs):
  35                 # Force the PAX format.
  36                 kwargs["format"] = tarfile.PAX_FORMAT
  37
  38                 tarfile.TarFile.__init__(self, *args, **kwargs)
  39
  40         def add(self, name, arcname=None, recursive=None, exclude=None, filter=None):
  41                 """
  42                         Emulate the add function with capability support.
  43                 """
  44                 tarinfo = self.gettarinfo(name, arcname)
  45
  46                 if tarinfo.isreg():
  47                         attrs = []
  48
  49                         # Save capabilities.
  50                         caps = util.get_capabilities(name)
  51                         if caps:
  52                                 log.debug("Saving capabilities for %s: %s" % (name, caps))
  53                                 tarinfo.pax_headers["PAKFIRE.capabilities"] = caps
  54
  55                         # Append the tar header and data to the archive.
  56                         f = tarfile.bltn_open(name, "rb")
  57                         self.addfile(tarinfo, f)
  58                         f.close()
  59
  60                 elif tarinfo.isdir():
  61                         self.addfile(tarinfo)
  62                         if recursive:
  63                                 for f in os.listdir(name):
  64                                         self.add(os.path.join(name, f), os.path.join(arcname, f),
  65                                                         recursive, exclude, filter)
  66
  67                 else:
  68                         self.addfile(tarinfo)
  69
  70                 # Return the tar information about the file
  71                 return tarinfo
  72
  73         def extract(self, member, path=""):
  74                 target = os.path.join(path, member.name)
  75
  76                 # Remove symlink targets, because tarfile cannot replace them.
  77                 if member.issym():
  78                         try:
  79                                 os.unlink(target)
  80                         except OSError:
  81                                 pass
  82
  83                 # Extract file the normal way...
  84                 try:
  85                         tarfile.TarFile.extract(self, member, path)
  86                 except OSError, e:
  87                         log.warning(_("Could not extract file: /%(src)s - %(dst)s") \
  88                                 % { "src" : member.name, "dst" : e, })
  89
  90                 if path:
  91                         target = os.path.join(path, member.name)
  92                 else:
  93                         target = "/%s" % member.name
  94
  95                 # ...and then apply the capabilities.
  96                 caps = member.pax_headers.get("PAKFIRE.capabilities", None)
  97                 if caps:
  98                         log.debug("Restoring capabilities for /%s: %s" % (member.name, caps))
  99                         util.set_capabilities(target, caps)
 100
 101
 102 class InnerTarFileXz(InnerTarFile):
 103         @classmethod
 104         def open(cls, name=None, mode="r", fileobj=None, **kwargs):
 105                 fileobj = lzma.LZMAFile(name, mode, fileobj=fileobj)
 106
 107                 try:
 108                         t = cls.taropen(name, mode, fileobj, **kwargs)
 109                 except lzma.LZMAError:
 110                         fileobj.close()
 111                         raise tarfile.ReadError("not an lzma file")
 112
 113                 t._extfileobj = False
 114                 return t