zutils/zcat.in

#! /bin/sh
# Zcat - Cat wrapper for compressed files.
# Copyright (C) 2009 Antonio Diaz Diaz.
#
# This script is free software: you have unlimited permission
# to copy, distribute and modify it.

LC_ALL=C
export LC_ALL
args=
two_hyphens=0

# Loop over args until a filename is found
while [ x"$1" != x ] ; do

	case "$1" in
	--help | --he* | -h)
		echo "Zcat - Cat wrapper for compressed files."
		echo
		echo "Zcat is a wrapper script around the cat command that allows"
		echo "transparent concatenation of any combination of compressed and"
		echo "non-compressed files. If any given file is compressed, its uncompressed"
		echo "content is used. If a given file does not exist, zcat tries the"
		echo "compressed file names corresponding to the supported compressors."
		echo "The supported compressors are gzip, bzip2, lzip and xz."
		echo
		echo "Usage: $0 [OPTIONS] [CAT_OPTIONS] [FILES]"
		echo
		echo "CAT_OPTIONS are passed directly to cat."
		echo "The exit status from cat is preserved."
		echo
		echo "Options:"
		echo "  -h, --help          display this help and exit"
		echo "  -V, --version       output version information and exit"
		echo
		echo "Report bugs to zutils-bug@nongnu.org"
		echo "Zutils home page: http://www.nongnu.org/zutils/zutils.html"
		exit 0 ;;
	--version | --ve* | -V)
		echo "Zcat VERSION"
		echo "Copyright (C) 2009 Antonio Diaz Diaz."
		echo "This script is free software: you have unlimited permission"
		echo "to copy, distribute and modify it."
		exit 0 ;;
	-)
		;;
	--)
		shift ; two_hyphens=1 ; break ;;
	-?*)
		args="${args} $1" ;;
	 *)
		break ;;
	esac
	shift
done


retval=0
for i in "$@" ; do
	if [ "$i" = "--" ] && [ ${two_hyphens} = 0 ] ; then two_hyphens=1
	else
		if [ ! -f "$i" ]; then
			if [ -f "$i.gz" ];    then i="$i.gz"
			elif [ -f "$i.bz2" ]; then i="$i.bz2"
			elif [ -f "$i.lz" ];  then i="$i.lz"
			elif [ -f "$i.xz" ];  then i="$i.xz"
			else
				echo "$0: File \"$i\" not found or not a regular file" 1>&2
				if [ ${retval} = 0 ]; then retval=1 ; fi
				continue
			fi
		fi
		bindir=`echo "$0" | sed -e 's,[^/]*$,,'`
		prog_name=`"${bindir}"zutils -t -- "$i"`
		case "${prog_name}" in
		gzip)	prog="gzip -cdfq" ;;
		bzip2)	prog="bzip2 -cdfq" ;;
		lzip)	prog="lzip -cdfq" ;;
		xz)	prog="xz -cdfq" ;;
		*)	prog=cat ;;
		esac
		${prog} -- "$i" | cat ${args}
		r=$?
		if [ $r != 0 ]; then retval=$r ; fi
	fi
done

exit ${retval}