eclass/unpacker.eclass - mirrors/cros/chromiumos/overlays/portage-stable - Git at Google

 # Copyright 1999-2013 Gentoo Foundation
 # Distributed under the terms of the GNU General Public License v2
 # $Header: /var/cvsroot/gentoo-x86/eclass/unpacker.eclass,v 1.14 2013/12/22 14:44:07 vapier Exp $

 # @ECLASS: unpacker.eclass
 # @MAINTAINER:
 # base-system@gentoo.org
 # @BLURB: helpers for extraneous file formats and consistent behavior across EAPIs
 # @DESCRIPTION:
 # Some extraneous file formats are not part of PMS, or are only in certain
 # EAPIs.  Rather than worrying about that, support the crazy cruft here
 # and for all EAPI versions.

 # Possible todos:
 #  - merge rpm unpacking
 #  - support partial unpacks?

 if [[ ${___ECLASS_ONCE_UNPACKER} != "recur -_+^+_- spank" ]] ; then
 ___ECLASS_ONCE_UNPACKER="recur -_+^+_- spank"

 # @ECLASS-VARIABLE: UNPACKER_BZ2
 # @DEFAULT_UNSET
 # @DESCRIPTION:
 # Utility to use to decompress bzip2 files.  Will dynamically pick between
 # `pbzip2` and `bzip2`.  Make sure your choice accepts the "-dc" options.
 # Note: this is meant for users to set, not ebuilds.

 # for internal use only (unpack_pdv and unpack_makeself)
 find_unpackable_file() {
 	local src=$1
 	if [[ -z ${src} ]] ; then
 		src=${DISTDIR}/${A}
 	else
 		if [[ ${src} == ./* ]] ; then
 			: # already what we want
 		elif [[ -e ${DISTDIR}/${src} ]] ; then
 			src=${DISTDIR}/${src}
 		elif [[ -e ${PWD}/${src} ]] ; then
 			src=${PWD}/${src}
 		elif [[ -e ${src} ]] ; then
 			src=${src}
 		fi
 	fi
 	[[ ! -e ${src} ]] && return 1
 	echo "${src}"
 }

 unpack_banner() {
 	echo ">>> Unpacking ${1##*/} to ${PWD}"
 }

 # @FUNCTION: unpack_pdv
 # @USAGE: <file to unpack> <size of off_t>
 # @DESCRIPTION:
 # Unpack those pesky pdv generated files ...
 # They're self-unpacking programs with the binary package stuffed in
 # the middle of the archive.  Valve seems to use it a lot ... too bad
 # it seems to like to segfault a lot :(.  So lets take it apart ourselves.
 #
 # You have to specify the off_t size ... I have no idea how to extract that
 # information out of the binary executable myself.  Basically you pass in
 # the size of the off_t type (in bytes) on the machine that built the pdv
 # archive.
 #
 # One way to determine this is by running the following commands:
 #
 # @CODE
 # 	strings <pdv archive> | grep lseek
 # 	strace -elseek <pdv archive>
 # @CODE
 #
 # Basically look for the first lseek command (we do the strings/grep because
 # sometimes the function call is _llseek or something) and steal the 2nd
 # parameter.  Here is an example:
 #
 # @CODE
 # 	$ strings hldsupdatetool.bin | grep lseek
 # 	lseek
 # 	$ strace -elseek ./hldsupdatetool.bin
 # 	lseek(3, -4, SEEK_END)					= 2981250
 # @CODE
 #
 # Thus we would pass in the value of '4' as the second parameter.
 unpack_pdv() {
 	local src=$(find_unpackable_file "$1")
 	local sizeoff_t=$2

 	[[ -z ${src} ]] && die "Could not locate source for '$1'"
 	[[ -z ${sizeoff_t} ]] && die "No idea what off_t size was used for this pdv :("

 	unpack_banner "${src}"

 	local metaskip=$(tail -c ${sizeoff_t} "${src}" | hexdump -e \"%i\")
 	local tailskip=$(tail -c $((${sizeoff_t}*2)) "${src}" | head -c ${sizeoff_t} | hexdump -e \"%i\")

 	# grab metadata for debug reasons
 	local metafile="${T}/${FUNCNAME}.meta"
 	tail -c +$((${metaskip}+1)) "${src}" > "${metafile}"

 	# rip out the final file name from the metadata
 	local datafile=$(tail -c +$((${metaskip}+1)) "${src}" | strings | head -n 1)
 	datafile=$(basename "${datafile}")

 	# now lets uncompress/untar the file if need be
 	local tmpfile="${T}/${FUNCNAME}"
 	tail -c +$((${tailskip}+1)) ${src} 2>/dev/null | head -c 512 > "${tmpfile}"

 	local iscompressed=$(file -b "${tmpfile}")
 	if [[ ${iscompressed:0:8} == "compress" ]] ; then
 		iscompressed=1
 		mv "${tmpfile}"{,.Z}
 		gunzip "${tmpfile}"
 	else
 		iscompressed=0
 	fi
 	local istar=$(file -b "${tmpfile}")
 	if [[ ${istar:0:9} == "POSIX tar" ]] ; then
 		istar=1
 	else
 		istar=0
 	fi

 	#for some reason gzip dies with this ... dd cant provide buffer fast enough ?
 	#dd if=${src} ibs=${metaskip} count=1 \
 	#	| dd ibs=${tailskip} skip=1 \
 	#	| gzip -dc \
 	#	> ${datafile}
 	if [ ${iscompressed} -eq 1 ] ; then
 		if [ ${istar} -eq 1 ] ; then
 			tail -c +$((${tailskip}+1)) "${src}" 2>/dev/null \
 				| head -c $((${metaskip}-${tailskip})) \
 				| tar -xzf -
 		else
 			tail -c +$((${tailskip}+1)) "${src}" 2>/dev/null \
 				| head -c $((${metaskip}-${tailskip})) \
 				| gzip -dc \
 				> ${datafile}
 		fi
 	else
 		if [ ${istar} -eq 1 ] ; then
 			tail -c +$((${tailskip}+1)) "${src}" 2>/dev/null \
 				| head -c $((${metaskip}-${tailskip})) \
 				| tar --no-same-owner -xf -
 		else
 			tail -c +$((${tailskip}+1)) "${src}" 2>/dev/null \
 				| head -c $((${metaskip}-${tailskip})) \
 				> ${datafile}
 		fi
 	fi
 	true
 	#[ -s "${datafile}" ] || die "failure unpacking pdv ('${metaskip}' '${tailskip}' '${datafile}')"
 	#assert "failure unpacking pdv ('${metaskip}' '${tailskip}' '${datafile}')"
 }

 # @FUNCTION: unpack_makeself
 # @USAGE: [file to unpack] [offset] [tail|dd]
 # @DESCRIPTION:
 # Unpack those pesky makeself generated files ...
 # They're shell scripts with the binary package tagged onto
 # the end of the archive.  Loki utilized the format as does
 # many other game companies.
 #
 # If the file is not specified, then ${A} is used.  If the
 # offset is not specified then we will attempt to extract
 # the proper offset from the script itself.
 unpack_makeself() {
 	local src_input=${1:-${A}}
 	local src=$(find_unpackable_file "${src_input}")
 	local skip=$2
 	local exe=$3

 	[[ -z ${src} ]] && die "Could not locate source for '${src_input}'"

 	unpack_banner "${src}"

 	if [[ -z ${skip} ]] ; then
 		local ver=$(grep -m1 -a '#.*Makeself' "${src}" | awk '{print $NF}')
 		local skip=0
 		exe=tail
 		case ${ver} in
 			1.5.*|1.6.0-nv*)	# tested 1.5.{3,4,5} ... guessing 1.5.x series is same
 				skip=$(grep -a ^skip= "${src}" | cut -d= -f2)
 				;;
 			2.0|2.0.1)
 				skip=$(grep -a ^$'\t'tail "${src}" | awk '{print $2}' | cut -b2-)
 				;;
 			2.1.1)
 				skip=$(grep -a ^offset= "${src}" | awk '{print $2}' | cut -b2-)
 				(( skip++ ))
 				;;
 			2.1.2)
 				skip=$(grep -a ^offset= "${src}" | awk '{print $3}' | head -n 1)
 				(( skip++ ))
 				;;
 			2.1.3)
 				skip=`grep -a ^offset= "${src}" | awk '{print $3}'`
 				(( skip++ ))
 				;;
 			2.1.4|2.1.5|2.1.6)
 				skip=$(grep -a offset=.*head.*wc "${src}" | awk '{print $3}' | head -n 1)
 				skip=$(head -n ${skip} "${src}" | wc -c)
 				exe="dd"
 				;;
 			*)
 				eerror "I'm sorry, but I was unable to support the Makeself file."
 				eerror "The version I detected was '${ver}'."
 				eerror "Please file a bug about the file ${src##*/} at"
 				eerror "http://bugs.gentoo.org/ so that support can be added."
 				die "makeself version '${ver}' not supported"
 				;;
 		esac
 		debug-print "Detected Makeself version ${ver} ... using ${skip} as offset"
 	fi
 	case ${exe} in
 		tail)	exe="tail -n +${skip} '${src}'";;
 		dd)		exe="dd ibs=${skip} skip=1 if='${src}'";;
 		*)		die "makeself cant handle exe '${exe}'"
 	esac

 	# lets grab the first few bytes of the file to figure out what kind of archive it is
 	local filetype tmpfile="${T}/${FUNCNAME}"
 	eval ${exe} 2>/dev/null | head -c 512 > "${tmpfile}"
 	filetype=$(file -b "${tmpfile}") || die
 	case ${filetype} in
 		*tar\ archive*)
 			eval ${exe} | tar --no-same-owner -xf -
 			;;
 		bzip2*)
 			eval ${exe} | bzip2 -dc | tar --no-same-owner -xf -
 			;;
 		gzip*)
 			eval ${exe} | tar --no-same-owner -xzf -
 			;;
 		compress*)
 			eval ${exe} | gunzip | tar --no-same-owner -xf -
 			;;
 		XZ*)
 			eval ${exe} | unxz | tar --no-same-owner -xf -
 			;;
 		*)
 			eerror "Unknown filetype \"${filetype}\" ?"
 			false
 			;;
 	esac
 	assert "failure unpacking (${filetype}) makeself ${src##*/} ('${ver}' +${skip})"
 }

 # @FUNCTION: unpack_deb
 # @USAGE: <one deb to unpack>
 # @DESCRIPTION:
 # Unpack a Debian .deb archive in style.
 unpack_deb() {
 	[[ $# -eq 1 ]] || die "Usage: ${FUNCNAME} <file>"

 	local deb=$(find_unpackable_file "$1")

 	unpack_banner "${deb}"

 	# on AIX ar doesn't work out as their ar used a different format
 	# from what GNU ar (and thus what .deb files) produce
 	if [[ -n ${EPREFIX} ]] ; then
 		{
 			read # global header
 			[[ ${REPLY} = "!<arch>" ]] || die "${deb} does not seem to be a deb archive"
 			local f timestamp uid gid mode size magic
 			while read f timestamp uid gid mode size magic ; do
 				[[ -n ${f} && -n ${size} ]] || continue # ignore empty lines
 				if [[ ${f} = "data.tar"* ]] ; then
 					head -c "${size}" > "${f}"
 				else
 					head -c "${size}" > /dev/null # trash it
 				fi
 			done
 		} < "${deb}"
 	else
 		ar x "${deb}"
 	fi

 	unpacker ./data.tar*

 	# Clean things up #458658.  No one seems to actually care about
 	# these, so wait until someone requests to do something else ...
 	rm -f debian-binary {control,data}.tar*
 }

 # @FUNCTION: unpack_cpio
 # @USAGE: <one cpio to unpack>
 # @DESCRIPTION:
 # Unpack a cpio archive, file "-" means stdin.
 unpack_cpio() {
 	[[ $# -eq 1 ]] || die "Usage: ${FUNCNAME} <file>"

 	# needed as cpio always reads from stdin
 	local cpio_cmd=( cpio --make-directories --extract --preserve-modification-time )
 	if [[ $1 == "-" ]] ; then
 		unpack_banner "stdin"
 		"${cpio_cmd[@]}"
 	else
 		local cpio=$(find_unpackable_file "$1")
 		unpack_banner "${cpio}"
 		"${cpio_cmd[@]}" <"${cpio}"
 	fi
 }

 # @FUNCTION: unpack_zip
 # @USAGE: <zip file>
 # @DESCRIPTION:
 # Unpack zip archives.
 # This function ignores all non-fatal errors (i.e. warnings).
 # That is useful for zip archives with extra crap attached
 # (e.g. self-extracting archives).
 unpack_zip() {
 	[[ $# -eq 1 ]] || die "Usage: ${FUNCNAME} <file>"

 	local zip=$(find_unpackable_file "$1")
 	unpack_banner "${zip}"
 	unzip -qo "${zip}"

 	[[ $? -le 1 ]] || die "unpacking ${zip} failed (arch=unpack_zip)"
 }

 # @FUNCTION: _unpacker
 # @USAGE: <one archive to unpack>
 # @INTERNAL
 # @DESCRIPTION:
 # Unpack the specified archive.  We only operate on one archive here
 # to keep down on the looping logic (that is handled by `unpacker`).
 _unpacker() {
 	[[ $# -eq 1 ]] || die "Usage: ${FUNCNAME} <file>"

 	local a=$1
 	local m=$(echo "${a}" | tr '[:upper:]' '[:lower:]')
 	a=$(find_unpackable_file "${a}")

 	# first figure out the decompression method
 	case ${m} in
 	*.bz2|*.tbz|*.tbz2)
 		local bzcmd=${PORTAGE_BZIP2_COMMAND:-$(type -P pbzip2 || type -P bzip2)}
 		local bzuncmd=${PORTAGE_BUNZIP2_COMMAND:-${bzcmd} -d}
 		: ${UNPACKER_BZ2:=${bzuncmd}}
 		comp="${UNPACKER_BZ2} -c"
 		;;
 	*.z|*.gz|*.tgz)
 		comp="gzip -dc" ;;
 	*.lzma|*.xz|*.txz)
 		comp="xz -dc" ;;
 	*)	comp="" ;;
 	esac

 	# then figure out if there are any archiving aspects
 	arch=""
 	case ${m} in
 	*.tgz|*.tbz|*.tbz2|*.txz|*.tar.*|*.tar)
 		arch="tar --no-same-owner -xof" ;;
 	*.cpio.*|*.cpio)
 		arch="unpack_cpio" ;;
 	*.deb)
 		arch="unpack_deb" ;;
 	*.run)
 		arch="unpack_makeself" ;;
 	*.sh)
 		# Not all shell scripts are makeself
 		if head -n 30 "${a}" | grep -qs '#.*Makeself' ; then
 			arch="unpack_makeself"
 		fi
 		;;
 	*.bin)
 		# Makeself archives can be annoyingly named
 		if head -c 100 "${a}" | grep -qs '#.*Makeself' ; then
 			arch="unpack_makeself"
 		fi
 		;;
 	*.zip)
 		arch="unpack_zip" ;;
 	esac

 	# finally do the unpack
 	if [[ -z ${arch}${comp} ]] ; then
 		unpack "$1"
 		return $?
 	fi

 	[[ ${arch} != unpack_* ]] && unpack_banner "${a}"

 	if [[ -z ${arch} ]] ; then
 		# Need to decompress the file into $PWD #408801
 		local _a=${a%.*}
 		${comp} "${a}" > "${_a##*/}"
 	elif [[ -z ${comp} ]] ; then
 		${arch} "${a}"
 	else
 		${comp} "${a}" | ${arch} -
 	fi

 	assert "unpacking ${a} failed (comp=${comp} arch=${arch})"
 }

 # @FUNCTION: unpacker
 # @USAGE: [archives to unpack]
 # @DESCRIPTION:
 # This works in the same way that `unpack` does.  If you don't specify
 # any files, it will default to ${A}.
 unpacker() {
 	local a
 	[[ $# -eq 0 ]] && set -- ${A}
 	for a ; do _unpacker "${a}" ; done
 }

 # @FUNCTION: unpacker_src_unpack
 # @DESCRIPTION:
 # Run `unpacker` to unpack all our stuff.
 unpacker_src_unpack() {
 	unpacker
 }

 # @FUNCTION: unpacker_src_uri_depends
 # @USAGE: [archives that we will unpack]
 # @RETURN: Dependencies needed to unpack all the archives
 # @DESCRIPTION:
 # Walk all the specified files (defaults to $SRC_URI) and figure out the
 # dependencies that are needed to unpack things.
 #
 # Note: USE flags are not yet handled.
 unpacker_src_uri_depends() {
 	local uri deps d

 	[[ $# -eq 0 ]] && set -- ${SRC_URI}

 	for uri in "$@" ; do
 		case ${uri} in
 		*.cpio.*|*.cpio)
 			d="app-arch/cpio" ;;
 		*.rar|*.RAR)
 			d="app-arch/unrar" ;;
 		*.7z)
 			d="app-arch/p7zip" ;;
 		*.xz)
 			d="app-arch/xz-utils" ;;
 		*.zip)
 			d="app-arch/unzip" ;;
 		esac
 		deps+=" ${d}"
 	done

 	echo "${deps}"
 }

 EXPORT_FUNCTIONS src_unpack

 fi
	# Copyright 1999-2013 Gentoo Foundation
	# Distributed under the terms of the GNU General Public License v2
	# $Header: /var/cvsroot/gentoo-x86/eclass/unpacker.eclass,v 1.14 2013/12/22 14:44:07 vapier Exp $

	# @ECLASS: unpacker.eclass
	# @MAINTAINER:
	# base-system@gentoo.org
	# @BLURB: helpers for extraneous file formats and consistent behavior across EAPIs
	# @DESCRIPTION:
	# Some extraneous file formats are not part of PMS, or are only in certain
	# EAPIs. Rather than worrying about that, support the crazy cruft here
	# and for all EAPI versions.

	# Possible todos:
	# - merge rpm unpacking
	# - support partial unpacks?

	if [[ ${___ECLASS_ONCE_UNPACKER} != "recur -_+^+_- spank" ]] ; then
	___ECLASS_ONCE_UNPACKER="recur -_+^+_- spank"

	# @ECLASS-VARIABLE: UNPACKER_BZ2
	# @DEFAULT_UNSET
	# @DESCRIPTION:
	# Utility to use to decompress bzip2 files. Will dynamically pick between
	# `pbzip2` and `bzip2`. Make sure your choice accepts the "-dc" options.
	# Note: this is meant for users to set, not ebuilds.

	# for internal use only (unpack_pdv and unpack_makeself)
	find_unpackable_file() {
	local src=$1
	if [[ -z ${src} ]] ; then
	src=${DISTDIR}/${A}
	else
	if [[ ${src} == ./* ]] ; then
	: # already what we want
	elif [[ -e ${DISTDIR}/${src} ]] ; then
	src=${DISTDIR}/${src}
	elif [[ -e ${PWD}/${src} ]] ; then
	src=${PWD}/${src}
	elif [[ -e ${src} ]] ; then
	src=${src}
	fi
	fi
	[[ ! -e ${src} ]] && return 1
	echo "${src}"
	}

	unpack_banner() {
	echo ">>> Unpacking ${1##*/} to ${PWD}"
	}

	# @FUNCTION: unpack_pdv
	# @USAGE: <file to unpack> <size of off_t>
	# @DESCRIPTION:
	# Unpack those pesky pdv generated files ...
	# They're self-unpacking programs with the binary package stuffed in
	# the middle of the archive. Valve seems to use it a lot ... too bad
	# it seems to like to segfault a lot :(. So lets take it apart ourselves.
	#
	# You have to specify the off_t size ... I have no idea how to extract that
	# information out of the binary executable myself. Basically you pass in
	# the size of the off_t type (in bytes) on the machine that built the pdv
	# archive.
	#
	# One way to determine this is by running the following commands:
	#
	# @CODE
	# strings <pdv archive> \| grep lseek
	# strace -elseek <pdv archive>
	# @CODE
	#
	# Basically look for the first lseek command (we do the strings/grep because
	# sometimes the function call is _llseek or something) and steal the 2nd
	# parameter. Here is an example:
	#
	# @CODE
	# $ strings hldsupdatetool.bin \| grep lseek
	# lseek
	# $ strace -elseek ./hldsupdatetool.bin
	# lseek(3, -4, SEEK_END) = 2981250
	# @CODE
	#
	# Thus we would pass in the value of '4' as the second parameter.
	unpack_pdv() {
	local src=$(find_unpackable_file "$1")
	local sizeoff_t=$2

	[[ -z ${src} ]] && die "Could not locate source for '$1'"
	[[ -z ${sizeoff_t} ]] && die "No idea what off_t size was used for this pdv :("

	unpack_banner "${src}"

	local metaskip=$(tail -c ${sizeoff_t} "${src}" \| hexdump -e \"%i\")
	local tailskip=$(tail -c $((${sizeoff_t}*2)) "${src}" \| head -c ${sizeoff_t} \| hexdump -e \"%i\")

	# grab metadata for debug reasons
	local metafile="${T}/${FUNCNAME}.meta"
	tail -c +$((${metaskip}+1)) "${src}" > "${metafile}"

	# rip out the final file name from the metadata
	local datafile=$(tail -c +$((${metaskip}+1)) "${src}" \| strings \| head -n 1)
	datafile=$(basename "${datafile}")

	# now lets uncompress/untar the file if need be
	local tmpfile="${T}/${FUNCNAME}"
	tail -c +$((${tailskip}+1)) ${src} 2>/dev/null \| head -c 512 > "${tmpfile}"

	local iscompressed=$(file -b "${tmpfile}")
	if [[ ${iscompressed:0:8} == "compress" ]] ; then
	iscompressed=1
	mv "${tmpfile}"{,.Z}
	gunzip "${tmpfile}"
	else
	iscompressed=0
	fi
	local istar=$(file -b "${tmpfile}")
	if [[ ${istar:0:9} == "POSIX tar" ]] ; then
	istar=1
	else
	istar=0
	fi

	#for some reason gzip dies with this ... dd cant provide buffer fast enough ?
	#dd if=${src} ibs=${metaskip} count=1 \
	# \| dd ibs=${tailskip} skip=1 \
	# \| gzip -dc \
	# > ${datafile}
	if [ ${iscompressed} -eq 1 ] ; then
	if [ ${istar} -eq 1 ] ; then
	tail -c +$((${tailskip}+1)) "${src}" 2>/dev/null \
	\| head -c $((${metaskip}-${tailskip})) \
	\| tar -xzf -
	else
	tail -c +$((${tailskip}+1)) "${src}" 2>/dev/null \
	\| head -c $((${metaskip}-${tailskip})) \
	\| gzip -dc \
	> ${datafile}
	fi
	else
	if [ ${istar} -eq 1 ] ; then
	tail -c +$((${tailskip}+1)) "${src}" 2>/dev/null \
	\| head -c $((${metaskip}-${tailskip})) \
	\| tar --no-same-owner -xf -
	else
	tail -c +$((${tailskip}+1)) "${src}" 2>/dev/null \
	\| head -c $((${metaskip}-${tailskip})) \
	> ${datafile}
	fi
	fi
	true
	#[ -s "${datafile}" ] \|\| die "failure unpacking pdv ('${metaskip}' '${tailskip}' '${datafile}')"
	#assert "failure unpacking pdv ('${metaskip}' '${tailskip}' '${datafile}')"
	}

	# @FUNCTION: unpack_makeself
	# @USAGE: [file to unpack] [offset] [tail\|dd]
	# @DESCRIPTION:
	# Unpack those pesky makeself generated files ...
	# They're shell scripts with the binary package tagged onto
	# the end of the archive. Loki utilized the format as does
	# many other game companies.
	#
	# If the file is not specified, then ${A} is used. If the
	# offset is not specified then we will attempt to extract
	# the proper offset from the script itself.
	unpack_makeself() {
	local src_input=${1:-${A}}
	local src=$(find_unpackable_file "${src_input}")
	local skip=$2
	local exe=$3

	[[ -z ${src} ]] && die "Could not locate source for '${src_input}'"

	unpack_banner "${src}"

	if [[ -z ${skip} ]] ; then
	local ver=$(grep -m1 -a '#.*Makeself' "${src}" \| awk '{print $NF}')
	local skip=0
	exe=tail
	case ${ver} in
	1.5.\|1.6.0-nv) # tested 1.5.{3,4,5} ... guessing 1.5.x series is same
	skip=$(grep -a ^skip= "${src}" \| cut -d= -f2)
	;;
	2.0\|2.0.1)
	skip=$(grep -a ^$'\t'tail "${src}" \| awk '{print $2}' \| cut -b2-)
	;;
	2.1.1)
	skip=$(grep -a ^offset= "${src}" \| awk '{print $2}' \| cut -b2-)
	(( skip++ ))
	;;
	2.1.2)
	skip=$(grep -a ^offset= "${src}" \| awk '{print $3}' \| head -n 1)
	(( skip++ ))
	;;
	2.1.3)
	skip=`grep -a ^offset= "${src}" \| awk '{print $3}'`
	(( skip++ ))
	;;
	2.1.4\|2.1.5\|2.1.6)
	skip=$(grep -a offset=.head.wc "${src}" \| awk '{print $3}' \| head -n 1)
	skip=$(head -n ${skip} "${src}" \| wc -c)
	exe="dd"
	;;
	*)
	eerror "I'm sorry, but I was unable to support the Makeself file."
	eerror "The version I detected was '${ver}'."
	eerror "Please file a bug about the file ${src##*/} at"
	eerror "http://bugs.gentoo.org/ so that support can be added."
	die "makeself version '${ver}' not supported"
	;;
	esac
	debug-print "Detected Makeself version ${ver} ... using ${skip} as offset"
	fi
	case ${exe} in
	tail) exe="tail -n +${skip} '${src}'";;
	dd) exe="dd ibs=${skip} skip=1 if='${src}'";;
	*) die "makeself cant handle exe '${exe}'"
	esac

	# lets grab the first few bytes of the file to figure out what kind of archive it is
	local filetype tmpfile="${T}/${FUNCNAME}"
	eval ${exe} 2>/dev/null \| head -c 512 > "${tmpfile}"
	filetype=$(file -b "${tmpfile}") \|\| die
	case ${filetype} in
	tar\ archive)
	eval ${exe} \| tar --no-same-owner -xf -
	;;
	bzip2*)
	eval ${exe} \| bzip2 -dc \| tar --no-same-owner -xf -
	;;
	gzip*)
	eval ${exe} \| tar --no-same-owner -xzf -
	;;
	compress*)
	eval ${exe} \| gunzip \| tar --no-same-owner -xf -
	;;
	XZ*)
	eval ${exe} \| unxz \| tar --no-same-owner -xf -
	;;
	*)
	eerror "Unknown filetype \"${filetype}\" ?"
	false
	;;
	esac
	assert "failure unpacking (${filetype}) makeself ${src##*/} ('${ver}' +${skip})"
	}

	# @FUNCTION: unpack_deb
	# @USAGE: <one deb to unpack>
	# @DESCRIPTION:
	# Unpack a Debian .deb archive in style.
	unpack_deb() {
	[[ $# -eq 1 ]] \|\| die "Usage: ${FUNCNAME} <file>"

	local deb=$(find_unpackable_file "$1")

	unpack_banner "${deb}"

	# on AIX ar doesn't work out as their ar used a different format
	# from what GNU ar (and thus what .deb files) produce
	if [[ -n ${EPREFIX} ]] ; then
	{
	read # global header
	[[ ${REPLY} = "!<arch>" ]] \|\| die "${deb} does not seem to be a deb archive"
	local f timestamp uid gid mode size magic
	while read f timestamp uid gid mode size magic ; do
	[[ -n ${f} && -n ${size} ]] \|\| continue # ignore empty lines
	if [[ ${f} = "data.tar"* ]] ; then
	head -c "${size}" > "${f}"
	else
	head -c "${size}" > /dev/null # trash it
	fi
	done
	} < "${deb}"
	else
	ar x "${deb}"
	fi

	unpacker ./data.tar*

	# Clean things up #458658. No one seems to actually care about
	# these, so wait until someone requests to do something else ...
	rm -f debian-binary {control,data}.tar*
	}

	# @FUNCTION: unpack_cpio
	# @USAGE: <one cpio to unpack>
	# @DESCRIPTION:
	# Unpack a cpio archive, file "-" means stdin.
	unpack_cpio() {
	[[ $# -eq 1 ]] \|\| die "Usage: ${FUNCNAME} <file>"

	# needed as cpio always reads from stdin
	local cpio_cmd=( cpio --make-directories --extract --preserve-modification-time )
	if [[ $1 == "-" ]] ; then
	unpack_banner "stdin"
	"${cpio_cmd[@]}"
	else
	local cpio=$(find_unpackable_file "$1")
	unpack_banner "${cpio}"
	"${cpio_cmd[@]}" <"${cpio}"
	fi
	}

	# @FUNCTION: unpack_zip
	# @USAGE: <zip file>
	# @DESCRIPTION:
	# Unpack zip archives.
	# This function ignores all non-fatal errors (i.e. warnings).
	# That is useful for zip archives with extra crap attached
	# (e.g. self-extracting archives).
	unpack_zip() {
	[[ $# -eq 1 ]] \|\| die "Usage: ${FUNCNAME} <file>"

	local zip=$(find_unpackable_file "$1")
	unpack_banner "${zip}"
	unzip -qo "${zip}"

	[[ $? -le 1 ]] \|\| die "unpacking ${zip} failed (arch=unpack_zip)"
	}

	# @FUNCTION: _unpacker
	# @USAGE: <one archive to unpack>
	# @INTERNAL
	# @DESCRIPTION:
	# Unpack the specified archive. We only operate on one archive here
	# to keep down on the looping logic (that is handled by `unpacker`).
	_unpacker() {
	[[ $# -eq 1 ]] \|\| die "Usage: ${FUNCNAME} <file>"

	local a=$1
	local m=$(echo "${a}" \| tr '[:upper:]' '[:lower:]')
	a=$(find_unpackable_file "${a}")

	# first figure out the decompression method
	case ${m} in
	.bz2\|.tbz\|*.tbz2)
	local bzcmd=${PORTAGE_BZIP2_COMMAND:-$(type -P pbzip2 \|\| type -P bzip2)}
	local bzuncmd=${PORTAGE_BUNZIP2_COMMAND:-${bzcmd} -d}
	: ${UNPACKER_BZ2:=${bzuncmd}}
	comp="${UNPACKER_BZ2} -c"
	;;
	.z\|.gz\|*.tgz)
	comp="gzip -dc" ;;
	.lzma\|.xz\|*.txz)
	comp="xz -dc" ;;
	*) comp="" ;;
	esac

	# then figure out if there are any archiving aspects
	arch=""
	case ${m} in
	.tgz\|.tbz\|.tbz2\|.txz\|.tar.\|*.tar)
	arch="tar --no-same-owner -xof" ;;
	.cpio.\|*.cpio)
	arch="unpack_cpio" ;;
	*.deb)
	arch="unpack_deb" ;;
	*.run)
	arch="unpack_makeself" ;;
	*.sh)
	# Not all shell scripts are makeself
	if head -n 30 "${a}" \| grep -qs '#.*Makeself' ; then
	arch="unpack_makeself"
	fi
	;;
	*.bin)
	# Makeself archives can be annoyingly named
	if head -c 100 "${a}" \| grep -qs '#.*Makeself' ; then
	arch="unpack_makeself"
	fi
	;;
	*.zip)
	arch="unpack_zip" ;;
	esac

	# finally do the unpack
	if [[ -z ${arch}${comp} ]] ; then
	unpack "$1"
	return $?
	fi

	[[ ${arch} != unpack_* ]] && unpack_banner "${a}"

	if [[ -z ${arch} ]] ; then
	# Need to decompress the file into $PWD #408801
	local _a=${a%.*}
	${comp} "${a}" > "${_a##*/}"
	elif [[ -z ${comp} ]] ; then
	${arch} "${a}"
	else
	${comp} "${a}" \| ${arch} -
	fi

	assert "unpacking ${a} failed (comp=${comp} arch=${arch})"
	}

	# @FUNCTION: unpacker
	# @USAGE: [archives to unpack]
	# @DESCRIPTION:
	# This works in the same way that `unpack` does. If you don't specify
	# any files, it will default to ${A}.
	unpacker() {
	local a
	[[ $# -eq 0 ]] && set -- ${A}
	for a ; do _unpacker "${a}" ; done
	}

	# @FUNCTION: unpacker_src_unpack
	# @DESCRIPTION:
	# Run `unpacker` to unpack all our stuff.
	unpacker_src_unpack() {
	unpacker
	}

	# @FUNCTION: unpacker_src_uri_depends
	# @USAGE: [archives that we will unpack]
	# @RETURN: Dependencies needed to unpack all the archives
	# @DESCRIPTION:
	# Walk all the specified files (defaults to $SRC_URI) and figure out the
	# dependencies that are needed to unpack things.
	#
	# Note: USE flags are not yet handled.
	unpacker_src_uri_depends() {
	local uri deps d

	[[ $# -eq 0 ]] && set -- ${SRC_URI}

	for uri in "$@" ; do
	case ${uri} in
	.cpio.\|*.cpio)
	d="app-arch/cpio" ;;
	.rar\|.RAR)
	d="app-arch/unrar" ;;
	*.7z)
	d="app-arch/p7zip" ;;
	*.xz)
	d="app-arch/xz-utils" ;;
	*.zip)
	d="app-arch/unzip" ;;
	esac
	deps+=" ${d}"
	done

	echo "${deps}"
	}

	EXPORT_FUNCTIONS src_unpack

	fi