• attachment:rewrite_faketime_tar_dates_script.txt of Mempo/mempo-deb/tar

   1 #!/bin/bash
   2 #
   3 # Rewrite a tar file with the time and owner from a reference file.
   4 #
   5 # Copyright (C) 2014 Ben Asselstine
   6 # This program is licensed under the terms of the GNU General Public License,
   7 # version 3, or at your option any later version. http://gnu.org/l/gpl-3.0.txt
   8 #
   9 # Caveats:
  10 #
  11 # This program only works with .tar.gz, .tgz, .tar.bz, and .tar.xz files.
  12 #
  13 # Only the first top-level directory in the archive has times modified
  14 # the old .tar file is kept in a .old backup file
  15 #
  16 # Req'd programs: coreutils (ls, mv, rm, head, mktemp, chown, touch), find, tar
  17 #
  18 
  19 # do we have the command line arguments?
  20 if [ ! -f $1 ]; then
  21         echo $0: file.tar.gz reference-file
  22         exit 1
  23 fi
  24 
  25 if [ ! -f $2 ]; then
  26         echo $0: file.tar.gz reference-file
  27         exit 1
  28 fi
  29 
  30 # do we support the compression method of the tar file?
  31 z=""
  32 if [[ $1 = *.tar.gz  || $1 = *.tgz ]] ; then
  33   z="z"
  34 elif [[ $1 = *.tar.bz ]] ; then
  35   z="j"
  36 elif [[ $1 = *.tar.xz ]] ; then
  37   z="J"
  38 else
  39   echo $0: file.tar.gz reference-file
  40   exit 1
  41 fi
  42 
  43 # take the owner and group from the reference file
  44 owner=`stat -c %U $2`
  45 group=`stat -c %G $2`
  46 
  47 # extract the tar file into a temporary directory
  48 dir=`mktemp -d /tmp/rewrite-tar.XXXXXX`
  49 tar --directory=$dir -${z}xvf $1
  50 if [ "$?" != "0" ]; then
  51         echo $0: failed to extract $1 to $dir
  52         exit 1
  53 fi
  54 
  55 # touch each of the files and directories in the first directory of the archive
  56 extracteddir=`ls $dir | head -n1`
  57 find $dir/$extracteddir -exec touch --reference=$2 {} \;
  58 
  59 # keep a backup of the old tar file
  60 mv $1 $1.old
  61 
  62 # recreate the tar file
  63 tar --directory=$dir --owner=$owner --group=$group -${z}cvf $1 $extracteddir
  64 
  65 chown $owner:$group $1
  66 touch --reference=$2 $1
  67 
  68 rm -rf $dir
  69 exit 0