busybox-links/zgrep

132 lines
3.7 KiB
Bash

#!/bin/sh
#
# Copyright (c) 2003 Thomas Klausner.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
# 1. Redistributions of source code must retain the above copyright
# notice, this list of conditions and the following disclaimer.
# 2. Redistributions in binary form must reproduce the above copyright
# notice, this list of conditions and the following disclaimer in the
# documentation and/or other materials provided with the distribution.
#
# THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
# IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
# OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
# IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
# NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
# THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
endofopts=0
pattern_found=0
grep_args=""
hyphen=0
silent=0
prog=${0##*/}
# handle being called 'zegrep' or 'zfgrep'
case $prog in
*egrep*) prog=zegrep; grep_args='-E';;
*fgrep*) prog=zfgrep; grep_args='-F';;
*) prog=zgrep;;
esac
# skip all options and pass them on to grep taking care of options
# with arguments, and if -e was supplied
while [ "$#" -gt 0 ] && [ "${endofopts}" -eq 0 ]; do
case "$1" in
# from GNU grep-2.5.1 -- keep in sync!
-[ABCDXdefm])
if [ "$#" -lt 2 ]; then
printf '%s: missing argument for %s flag\n' "${prog}" "$1" >&2
exit 1
fi
case "$1" in
-e)
pattern="$2"
pattern_found=1
shift 2
break
;;
-f)
pattern_found=2
;;
*)
;;
esac
grep_args="${grep_args} $1 $2"
shift 2
;;
--)
shift
endofopts=1
;;
-)
hyphen=1
shift
;;
-h)
silent=1
shift
;;
-*)
grep_args="${grep_args} $1"
shift
;;
*)
# pattern to grep for
endofopts=1
;;
esac
done
# if no -e option was found, take next argument as grep-pattern
if [ "${pattern_found}" -lt 1 ]; then
if [ "$#" -ge 1 ]; then
pattern="$1"
shift
elif [ "${hyphen}" -gt 0 ]; then
pattern="-"
else
printf '%s: missing pattern\n' "${prog}" >&2
exit 1
fi
fi
EXIT_CODE=0
# call grep ...
if [ "$#" -lt 1 ]; then
# ... on stdin
set -f # Disable file name generation (globbing).
# shellcheck disable=SC2086
"zcat" - | "grep" ${grep_args} -- "${pattern}" -
EXIT_CODE=$?
set +f
else
# ... on all files given on the command line
if [ "${silent}" -lt 1 ] && [ "$#" -gt 1 ]; then
grep_args="-H ${grep_args}"
fi
set -f
while [ "$#" -gt 0 ]; do
# shellcheck disable=SC2086
if [ $pattern_found -eq 2 ]; then
"zcat" -- "$1" | "grep" ${grep_args} -- -
else
"zcat" -- "$1" | "grep" ${grep_args} -- "${pattern}" -
fi
[ "$?" -ne 0 ] && EXIT_CODE=1
shift
done
set +f
fi
exit "${EXIT_CODE}"