gzexe.in

   1 #!/bin/sh
   2 # gzexe: compressor for Unix executables.
   3 # Use this only for binaries that you do not use frequently.
   4 #
   5 # The compressed version is a shell script which decompresses itself after
   6 # skipping $skip lines of shell commands.  We try invoking the compressed
   7 # executable with the original name (for programs looking at their name).
   8 # We also try to retain the original file permissions on the compressed file.
   9 # For safety reasons, gzexe will not create setuid or setgid shell scripts.
  10
  11 # WARNING: the first line of this file must be either : or #!/bin/sh
  12 # The : is required for some old versions of csh.
  13 # On Ultrix, /bin/sh is too buggy, change the first line to: #!/bin/sh5
  14
  15
  16 # Copyright (C) 1998, 2002, 2004, 2006-2007, 2010-2022 Free Software
  17 # Foundation, Inc.
  18 # Copyright (C) 1993 Jean-loup Gailly
  19
  20 # This program is free software; you can redistribute it and/or modify
  21 # it under the terms of the GNU General Public License as published by
  22 # the Free Software Foundation; either version 3 of the License, or
  23 # (at your option) any later version.
  24
  25 # This program is distributed in the hope that it will be useful,
  26 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  27 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  28 # GNU General Public License for more details.
  29
  30 # You should have received a copy of the GNU General Public License along
  31 # with this program; if not, write to the Free Software Foundation, Inc.,
  32 # 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  33
  34 tab='   '
  35 nl='
  36 '
  37 IFS=" $tab$nl"
  38
  39 version='gzexe (gzip) @VERSION@
  40 Copyright (C) 2007, 2011-2018 Free Software Foundation, Inc.
  41 This is free software.  You may redistribute copies of it under the terms of
  42 the GNU General Public License <https://www.gnu.org/licenses/gpl.html>.
  43 There is NO WARRANTY, to the extent permitted by law.
  44
  45 Written by Jean-loup Gailly.'
  46
  47 usage="Usage: $0 [OPTION] FILE...
  48 Replace each executable FILE with a compressed version of itself.
  49 Make a backup FILE~ of the old version of FILE.
  50
  51   -d             Decompress each FILE instead of compressing it.
  52       --help     display this help and exit
  53       --version  output version information and exit
  54
  55 Report bugs to <bug-gzip@gnu.org>."
  56
  57 decomp=0
  58 res=0
  59 while :; do
  60   case $1 in
  61   -d) decomp=1; shift;;
  62   --h*) printf '%s\n' "$usage"   || exit 1; exit;;
  63   --v*) printf '%s\n' "$version" || exit 1; exit;;
  64   --) shift; break;;
  65   *) break;;
  66   esac
  67 done
  68
  69 if test $# -eq 0; then
  70   printf >&2 '%s\n' "$0: missing operand
  71 Try \`$0 --help' for more information."
  72   exit 1
  73 fi
  74
  75 tmp=
  76 trap 'res=$?
  77   test -n "$tmp" && rm -f "$tmp"
  78   (exit $res); exit $res
  79 ' 0 1 2 3 5 10 13 15
  80
  81 mktemp_status=
  82
  83 for i do
  84   case $i in
  85   -*) file=./$i;;
  86   *)  file=$i;;
  87   esac
  88   if test ! -f "$file" || test ! -r "$file"; then
  89     res=$?
  90     printf >&2 '%s\n' "$0: $i is not a readable regular file"
  91     continue
  92   fi
  93   if test $decomp -eq 0; then
  94     if sed -e 1d -e 2q "$file" | grep "^skip=[0-9][0-9]*$" >/dev/null; then
  95       printf >&2 '%s\n' "$0: $i is already gzexe'd"
  96       continue
  97     fi
  98   fi
  99   if test -u "$file"; then
 100     printf >&2 '%s\n' "$0: $i has setuid permission, unchanged"
 101     continue
 102   fi
 103   if test -g "$file"; then
 104     printf >&2 '%s\n' "$0: $i has setgid permission, unchanged"
 105     continue
 106   fi
 107   case /$file in
 108   */basename | */bash | */cat | */chmod | */cp | \
 109   */dirname | */expr | */gzip | \
 110   */ln | */mkdir | */mktemp | */mv | */printf | */rm | \
 111   */sed | */sh | */sleep | */test | */tail)
 112     printf >&2 '%s\n' "$0: $i might depend on itself"; continue;;
 113   esac
 114
 115   dir=`dirname "$file"` || dir=$TMPDIR
 116   test -d "$dir" && test -w "$dir" && test -x "$dir" || dir=/tmp
 117   test -n "$tmp" && rm -f "$tmp"
 118   if test -z "$mktemp_status"; then
 119     type mktemp >/dev/null 2>&1
 120     mktemp_status=$?
 121   fi
 122   case $dir in
 123     */) ;;
 124     *) dir=$dir/;;
 125   esac
 126   if test $mktemp_status -eq 0; then
 127     tmp=`mktemp "${dir}gzexeXXXXXXXXX"`
 128   else
 129     tmp=${dir}gzexe$$
 130   fi && { cp -p "$file" "$tmp" 2>/dev/null || cp "$file" "$tmp"; } || {
 131     res=$?
 132     printf >&2 '%s\n' "$0: cannot copy $file"
 133     continue
 134   }
 135   if test -w "$tmp"; then
 136     writable=1
 137   else
 138     writable=0
 139     chmod u+w "$tmp" || {
 140       res=$?
 141       printf >&2 '%s\n' "$0: cannot chmod $tmp"
 142       continue
 143     }
 144   fi
 145   if test $decomp -eq 0; then
 146     (cat <<'EOF' &&
 147 #!/bin/sh
 148 skip=49
 149
 150 tab='   '
 151 nl='
 152 '
 153 IFS=" $tab$nl"
 154
 155 umask=`umask`
 156 umask 77
 157
 158 gztmpdir=
 159 trap 'res=$?
 160   test -n "$gztmpdir" && rm -fr "$gztmpdir"
 161   (exit $res); exit $res
 162 ' 0 1 2 3 5 10 13 15
 163
 164 case $TMPDIR in
 165   / | /*/) ;;
 166   /*) TMPDIR=$TMPDIR/;;
 167   *) TMPDIR=/tmp/;;
 168 esac
 169 if type mktemp >/dev/null 2>&1; then
 170   gztmpdir=`mktemp -d "${TMPDIR}gztmpXXXXXXXXX"`
 171 else
 172   gztmpdir=${TMPDIR}gztmp$$; mkdir $gztmpdir
 173 fi || { (exit 127); exit 127; }
 174
 175 gztmp=$gztmpdir/$0
 176 case $0 in
 177 -* | */*'
 178 ') mkdir -p "$gztmp" && rm -r "$gztmp";;
 179 */*) gztmp=$gztmpdir/`basename "$0"`;;
 180 esac || { (exit 127); exit 127; }
 181
 182 case `printf 'X\n' | tail -n +1 2>/dev/null` in
 183 X) tail_n=-n;;
 184 *) tail_n=;;
 185 esac
 186 if tail $tail_n +$skip <"$0" | gzip -cd > "$gztmp"; then
 187   umask $umask
 188   chmod 700 "$gztmp"
 189   (sleep 5; rm -fr "$gztmpdir") 2>/dev/null &
 190   "$gztmp" ${1+"$@"}; res=$?
 191 else
 192   printf >&2 '%s\n' "Cannot decompress $0"
 193   (exit 127); res=127
 194 fi; exit $res
 195 EOF
 196     gzip -cv9 "$file") > "$tmp" || {
 197       res=$?
 198       printf >&2 '%s\n' "$0: compression not possible for $i, file unchanged."
 199       continue
 200     }
 201
 202   else
 203     # decompression
 204     skip=44
 205     skip_line=`sed -e 1d -e 2q "$file"`
 206     case $skip_line in
 207     skip=[0-9] | skip=[0-9][0-9] | skip=[0-9][0-9][0-9])
 208       eval "$skip_line";;
 209     esac
 210     case `printf 'X\n' | tail -n +1 2>/dev/null` in
 211     X) tail_n=-n;;
 212     *) tail_n=;;
 213     esac
 214     tail $tail_n +$skip "$file" | gzip -cd > "$tmp" || {
 215       res=$?
 216       printf >&2 '%s\n' "$0: $i probably not in gzexe format, file unchanged."
 217       continue
 218     }
 219   fi
 220   test $writable -eq 1 || chmod u-w "$tmp" || {
 221     res=$?
 222     printf >&2 '%s\n' "$0: $tmp: cannot chmod"
 223     continue
 224   }
 225   ln -f "$file" "$file~" 2>/dev/null || {
 226     # Hard links may not work.  Fall back on rm+cp so that $file always exists.
 227     rm -f "$file~" && cp -p "$file" "$file~"
 228   } || {
 229     res=$?
 230     printf >&2 '%s\n' "$0: cannot backup $i as $i~"
 231     continue
 232   }
 233   mv -f "$tmp" "$file" || {
 234     res=$?
 235     printf >&2 '%s\n' "$0: cannot rename $tmp to $i"
 236     continue
 237   }
 238   tmp=
 239 done
 240 (exit $res); exit $res