gzip/znew

   1 #!/bin/sh -
   2 #
   3 # $NetBSD: znew,v 1.3 2008/04/27 09:07:13 nakayama Exp $
   4 # $OpenBSD: znew,v 1.2 2003/08/05 18:22:17 deraadt Exp $
   5 #
   6 #-
   7 # Copyright (c) 2003 Otto Moerbeek <otto@drijf.net>
   8 #
   9 # Permission to use, copy, modify, and distribute this software for any
  10 # purpose with or without fee is hereby granted, provided that the above
  11 # copyright notice and this permission notice appear in all copies.
  12 #
  13 # THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  14 # WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  15 # MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  16 # ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  17 # WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  18 # ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  19 # OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  20 #
  21 # $FreeBSD: src/usr.bin/gzip/znew,v 1.3 2008/06/30 23:53:15 delphij Exp $
  22
  23 # Return 0 if the first arg file size is smaller than the second, 1 otherwise.
  24 smaller () {
  25         a=`du -k "$1" | awk '{ print $1 }'`
  26         b=`du -k "$2" | awk '{ print $1 }'`
  27         test $a -lt $b
  28 }
  29
  30 # Check gzip integrity if the -t flag is specified
  31 checkfile () {
  32         if test $tflag -eq 1; then
  33                 gzip -qt < "$1"
  34         fi
  35 }
  36
  37 # Decompress a file and then gzip it
  38 process () {
  39         prefix="${1%.Z}"
  40         filez="$prefix".Z
  41         filegz="$prefix".gz
  42
  43         if test ! -e "$filez"; then
  44                 echo "$prog: $filez does not exist"
  45                 return 1
  46         fi
  47         if test ! -f "$filez"; then
  48                 echo "$prog: $filez is not a regular file"
  49                 return 1
  50         fi
  51         if test -e "$filegz" -a $fflag -eq 0; then
  52                 echo "$prog: $filegz already exists"
  53                 return 1
  54         fi
  55
  56         tmp=`mktemp /tmp/znewXXXXXXXXXX` || {
  57                 echo "$prog: cannot create tmp file"
  58                 return 1
  59         }
  60         trap 'rm -f "$tmp"; exit 1' HUP INT QUIT PIPE TERM
  61
  62         # Do the actual work, producing a file "$tmp"
  63         if uncompress -f -c < "$filez" | gzip -f -c $gzipflags > "$tmp"; then
  64                 if test $kflag -eq 1 && smaller "$filez" "$tmp"; then
  65                         echo -n "$prog: $filez is smaller than $filegz"
  66                         echo "; keeping it"
  67                         rm -f "$tmp"
  68                         return 0
  69                 fi
  70                 if ! checkfile "$tmp"; then
  71                         echo "$prog: integrity check of $tmp failed"
  72                         rm -f "$tmp"
  73                         return 1;
  74                 fi
  75
  76                 # Try to keep the mode of the original file
  77                 if ! cp -fp "$filez" "$filegz"; then
  78                         echo "$prog: warning: could not keep mode of $filez"
  79                 fi
  80                 if  ! cp "$tmp" "$filegz" 2> /dev/null; then
  81                         echo "$prog: warning: could not keep mode of $filez"
  82                         if ! cp -f "$tmp" "$filegz" 2> /dev/null; then
  83                                 echo "$prog: could not copy $tmp to $filegz"
  84                                 rm -f "$filegz" "$tmp"
  85                                 return 1
  86                         fi
  87                 fi
  88                 if ! touch -fr "$filez" "$filegz"; then
  89                         echo -n "$prog: warning: could not keep timestamp of "
  90                         echo "$filez"
  91                 fi
  92                 rm -f "$filez" "$tmp"
  93         else
  94                 echo "$prog: failed to process $filez"
  95                 rm -f "$tmp"
  96                 return 1
  97         fi
  98 }
  99
 100 prog=`basename "$0"`
 101 usage="usage: $prog [-ftv9K] file ..."
 102
 103 fflag=0
 104 tflag=0
 105 kflag=0
 106 gzipflags=
 107
 108 # -P flag is recognized to maintain compatibility, but ignored. Pipe mode is
 109 # always used
 110 while getopts :ftv9PK i; do
 111         case $i in
 112                 f) fflag=1;;
 113                 t) tflag=1;;
 114                 v) gzipflags="-v $gzipflags";;
 115                 9) gzipflags="-9 $gzipflags";;
 116                 P) ;;
 117                 K) kflag=1;;
 118                 \?) echo "$usage"; exit 1;;
 119         esac
 120 done
 121
 122 shift $((OPTIND - 1))
 123
 124 if test $# -eq 0; then
 125         echo "$usage"
 126         exit 1
 127 fi
 128
 129 rc=0
 130
 131 while test $# -ne 0; do
 132         if ! process "$1"; then
 133                 rc=$?
 134         fi
 135         shift
 136 done
 137 exit $rc