packaging/utils/patcher

   1 #! /bin/sh
   2 # smart patch applier
   3 # Copyright (C) 1999, 2001  Henry Spencer.
   4 #
   5 # This program is free software; you can redistribute it and/or modify it
   6 # under the terms of the GNU General Public License as published by the
   7 # Free Software Foundation; either version 2 of the License, or (at your
   8 # option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
   9 #
  10 # This program is distributed in the hope that it will be useful, but
  11 # WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  12 # or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  13 # for more details.
  14 #
  15 # patcher [-v] [-c] targetdir target [ key patchfile ] ...
  16 # In targetdir, patch target from patchfile unless it already contains
  17 # key and it appears to have been patched with the same patch.  (If the
  18 # patch has changed, undo the old one and then put the new one in.)  Save
  19 # original as target.preipsec, and patched copy as target.wipsec, with
  20 # patch md5sum stored as target.ipsecmd5.  If the patch doesn't work,
  21 # put the original back and save the patch attempt as target.mangled.
  22 # If there are no key+patchfile pairs, undo any old patch and leave it
  23 # at that.
  24 # -v means verbose
  25 # -c means do "patching" by appending rather than by using patch(1)
  26 #
  27 # RCSID $Id: patcher,v 1.1 2004/03/15 20:35:27 as Exp $
  28
  29 PATH=/bin:/usr/bin:/usr/local/bin:/sbin:/usr/sbin:/usr/local/sbin
  30 export PATH
  31 umask 022
  32
  33 verbose=
  34 modifier=patch
  35 for dummy
  36 do
  37         case "$1" in
  38         -v)     verbose=yes             ;;
  39         -c)     modifier=cat            ;;
  40         --)     shift ; break           ;;
  41         -*)     echo "$0: unknown option \`$1'" >&2 ; exit 2    ;;
  42         *)      break                   ;;
  43         esac
  44         shift
  45 done
  46 if test $# -lt 2
  47 then
  48         echo "Usage: $0 [-v] [-c] targetdir target [ key patchfile ] ..." >&2
  49         exit 2
  50 fi
  51
  52 need() {
  53         if test ! -f $1
  54         then
  55                 echo "$0: cannot find file \`$1'" >&2
  56                 exit 1
  57         fi
  58 }
  59
  60 note() {
  61         if test "$verbose"
  62         then
  63                 echo "* $1"
  64         fi
  65 }
  66
  67 dir="$1"
  68 target="$2"
  69 shift ; shift
  70 it=$dir/$target
  71 need $it
  72
  73
  74
  75 patches=
  76 if test ! -s $it.ipsecmd5
  77 then
  78         # no records of patching...
  79         while test $# -ge 2
  80         do
  81                 key="$1"
  82                 patchfile="$2"
  83                 shift ; shift
  84                 need $patchfile
  85
  86                 if egrep -q "$key" $it
  87                 then
  88                         # patched but no record of how
  89                         note "$it no longer needs patch $patchfile"
  90                 else
  91                         patches="$patches $patchfile"
  92                 fi
  93         done
  94 elif test ! -f $it.preipsec -o ! -f $it.wipsec
  95 then
  96         echo "$0: $it.preipsec or .wipsec is missing!" >&2
  97         exit 1
  98 else
  99         # determine whether patches have changed
 100         tmp=/tmp/patcher.$$
 101         >$tmp
 102         while test $# -ge 2
 103         do
 104                 key="$1"
 105                 patchfile="$2"
 106                 shift ; shift
 107                 need $patchfile
 108                 md5sum $patchfile | awk '{print $1}' >>$tmp
 109
 110                 if egrep -q "$key" $it.preipsec
 111                 then
 112                         note "$it no longer needs patch $patchfile"
 113                 else
 114                         patches="$patches $patchfile"
 115                 fi
 116         done
 117         if cmp -s $tmp $it.ipsecmd5
 118         then
 119                 note "$it already fully patched"
 120                 rm -f $tmp
 121                 exit 0
 122         fi
 123         rm -f $tmp
 124
 125         # must undo old patch(es)
 126         note "$it old patches must be undone, undoing them..."
 127         if ! cmp -s $it $it.wipsec
 128         then
 129                 note "$it has changed, cannot undo old patches!"
 130                 echo "$0: cannot unpatch $it, it has changed since patching" >&2
 131                 exit 1
 132         fi
 133         rm $it
 134         mv $it.preipsec $it
 135         rm $it.wipsec $it.ipsecmd5
 136 fi
 137
 138 # if no necessary patches, we're done
 139 if test " $patches" = " "
 140 then
 141         note "$it no longer needs patching"
 142         exit 0
 143 fi
 144
 145 # try to figure out patch options
 146 if test " $modifier" = " patch"
 147 then
 148         if patch --help >/dev/null 2>/dev/null
 149         then
 150                 # looks like a modern version
 151                 popts='-p1 -b'
 152         else
 153                 # looks like an old one
 154                 popts='-p1'
 155         fi
 156 fi
 157
 158 # do it
 159 >$it.ipsecmd5
 160 for patchfile in $patches
 161 do
 162         note "applying $patchfile to $it..."
 163
 164         # make local copy - this defeats hard and soft links
 165         mv $it $it.preipsec || exit 0
 166         rm -f $it
 167         cp -p $it.preipsec $it
 168
 169         case "$modifier" in
 170         patch)  ( cd $dir ; patch $popts ) <$patchfile  ;;
 171         cat)    cat $patchfile >>$it                    ;;
 172         esac
 173         status=$?
 174         if test $status -ne 0
 175         then
 176                 note "$it patch failed, restoring original"
 177                 echo "$0: patch on $it failed!" >&2
 178                 echo "$0: restoring original $it," >&2
 179                 echo "$0: leaving patch attempt in $it.mangled" >&2
 180                 mv $it $it.mangled
 181                 mv $it.preipsec $it
 182                 rm -f $it.ipsecmd5
 183                 exit 1
 184         fi
 185         rm -f $it.orig          # some patch versions leave debris
 186         md5sum $patchfile | awk '{print $1}' >>$it.ipsecmd5
 187 done
 188 cp -p $it $it.wipsec