xref: /freebsd/usr.bin/gzip/znew (revision fcb560670601b2a4d87bb31d7531c8dcc37ee71b)
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# $FreeBSD$
22
23# Return 0 if the first arg file size is smaller than the second, 1 otherwise.
24smaller () {
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
31checkfile () {
32	if test $tflag -eq 1; then
33		gzip -qt < "$1"
34	fi
35}
36
37# Decompress a file and then gzip it
38process () {
39	prefix="${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
100prog=`basename "$0"`
101usage="usage: $prog [-ftv9K] file ..."
102
103fflag=0
104tflag=0
105kflag=0
106gzipflags=
107
108# -P flag is recognized to maintain compatibility, but ignored. Pipe mode is
109# always used
110while 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
120done
121
122shift $((OPTIND - 1))
123
124if test $# -eq 0; then
125	echo "$usage"
126	exit 1
127fi
128
129rc=0
130
131while test $# -ne 0; do
132	if ! process "$1"; then
133		rc=$?
134	fi
135	shift
136done
137exit $rc
138