#!/bin/sh
# gzexe: compressor for Unix executables.
# Use this only for binaries that you do not use frequently.
#
# The compressed version is a shell script which decompresses itself after
# skipping $skip lines of shell commands. We try invoking the compressed
# executable with the original name (for programs looking at their name).
# We also try to retain the original file permissions on the compressed file.
# For safety reasons, gzexe will not create setuid or setgid shell scripts.
# WARNING: the first line of this file must be either : or #!/bin/sh
# The : is required for some old versions of csh.
# On Ultrix, /bin/sh is too buggy, change the first line to: #!/bin/sh5
# Copyright (C) 1998, 2002 Free Software Foundation
# Copyright (C) 1993 Jean-loup Gailly
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2, or (at your option)
# any later version.
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
# 02111-1307, USA.
PATH="/usr/bin:$PATH"
x=`basename $0`
if test $# = 0; then
echo compress executables. original file foo is renamed to foo~
echo usage: ${x} [-d] files...
echo " -d decompress the executables"
exit 1
fi
set -C
tmp=gz$$
trap "rm -f $tmp; exit 1" HUP INT QUIT TRAP USR1 PIPE TERM
: > $tmp || exit 1
decomp=0
res=0
test "$x" = "ungzexe" && decomp=1
if test "x$1" = "x-d"; then
decomp=1
shift
fi
echo hi > zfoo1$$ || exit 1
echo hi > zfoo2$$ || exit 1
if test -z "`(${CPMOD-cpmod} zfoo1$$ zfoo2$$) 2>&1`"; then
cpmod=${CPMOD-cpmod}
fi
rm -f zfoo[12]$$
tail=""
IFS="${IFS= }"; saveifs="$IFS"; IFS="${IFS}:"
for dir in $PATH; do
test -z "$dir" && dir=.
if test -f $dir/tail; then
tail="$dir/tail"
break
fi
done
IFS="$saveifs"
if test -z "$tail"; then
echo cannot find tail
exit 1
fi
case `echo foo | $tail -n +1 2>/dev/null` in
foo) tail="$tail -n";;
esac
for i do
if test ! -f "$i" ; then
echo ${x}: $i not a file
res=1
continue
fi
if test $decomp -eq 0; then
if sed -e 1d -e 2q "$i" | grep "^skip=[0-9]*$" >/dev/null; then
echo "${x}: $i is already gzexe'd"
continue
fi
fi
if ls -l "$i" | grep '^...[sS]' > /dev/null; then
echo "${x}: $i has setuid permission, unchanged"
continue
fi
if ls -l "$i" | grep '^......[sS]' > /dev/null; then
echo "${x}: $i has setgid permission, unchanged"
continue
fi
case "`basename $i`" in
bzip2 | tail | sed | chmod | ln | sleep | rm)
echo "${x}: $i would depend on itself"; continue ;;
esac
if test -z "$cpmod"; then
cp -p "$i" $tmp 2>/dev/null || cp "$i" $tmp
if test -w $tmp 2>/dev/null; then
writable=1
else
writable=0
chmod u+w $tmp 2>/dev/null
fi
: >| $tmp # truncate the file, ignoring set -C
fi
if test $decomp -eq 0; then
sed 1q $0 >> $tmp
sed "s|^if tail|if $tail|" >> $tmp <<'EOF'
skip=23
set -C
umask=`umask`
umask 77
tmpfile=`tempfile -p gztmp -d /tmp` || exit 1
if tail +$skip "$0" | /bin/bzip2 -cd >> $tmpfile; then
umask $umask
/bin/chmod 700 $tmpfile
prog="`echo $0 | /bin/sed 's|^.*/||'`"
if /bin/ln -T $tmpfile "/tmp/$prog" 2>/dev/null; then
trap '/bin/rm -f $tmpfile "/tmp/$prog"; exit $res' 0
(/bin/sleep 5; /bin/rm -f $tmpfile "/tmp/$prog") 2>/dev/null &
/tmp/"$prog" ${1+"$@"}; res=$?
else
trap '/bin/rm -f $tmpfile; exit $res' 0
(/bin/sleep 5; /bin/rm -f $tmpfile) 2>/dev/null &
$tmpfile ${1+"$@"}; res=$?
fi
else
echo Cannot decompress $0; exit 1
fi; exit $res
EOF
bzip2 -cv9 "$i" >> $tmp || {
/bin/rm -f $tmp
echo ${x}: compression not possible for $i, file unchanged.
res=1
continue
}
else
# decompression
skip=23
if sed -e 1d -e 2q "$i" | grep "^skip=[0-9]*$" >/dev/null; then
eval `sed -e 1d -e 2q "$i"`
fi
if tail +$skip "$i" | bzip2 -cd > $tmp; then
:
else
echo ${x}: $i probably not in gzexe format, file unchanged.
res=1
continue
fi
fi
rm -f "$i~"
mv "$i" "$i~" || {
echo ${x}: cannot backup $i as $i~
rm -f $tmp
res=1
continue
}
mv $tmp "$i" || cp -p $tmp "$i" 2>/dev/null || cp $tmp "$i" || {
echo ${x}: cannot create $i
rm -f $tmp
res=1
continue
}
rm -f $tmp
if test -n "$cpmod"; then
$cpmod "$i~" "$i" 2>/dev/null
elif test $writable -eq 0; then
chmod u-w $i 2>/dev/null
fi
done
exit $res
Mini Shell