path: root/eclass/kernel-2.eclass

# Copyright 1999-2005 Gentoo Foundation
# Distributed under the terms of the GNU General Public License v2
# $Header: /var/cvsroot/gentoo-x86/eclass/kernel-2.eclass,v 1.84 2005/01/14 12:15:15 johnm Exp $

# Description: kernel.eclass rewrite for a clean base regarding the 2.6
#              series of kernel with back-compatibility for 2.4
#
# Maintainer: John Mylchreest <johnm@gentoo.org>
#
# Please direct your bugs to the current eclass maintainer :)

# added functionality:
# unipatch		- a flexible, singular method to extract, add and remove patches.

# A Couple of env vars are available to effect usage of this eclass
# These are as follows:
#
# K_NOSETEXTRAVERSION	- if this is set then EXTRAVERSION will not be
#						  automatically set within the kernel Makefile
# K_NOUSENAME			- if this is set then EXTRAVERSION will not include the
#						  first part of ${PN} in EXTRAVERSION
# K_PREPATCHED			- if the patchset is prepatched (ie: mm-sources,
#						  ck-sources, ac-sources) it will use PR (ie: -r5) as
#						  the patchset version for
#						- and not use it as a true package revision
# K_EXTRAEINFO			- this is a new-line seperated list of einfo displays in
#						  postinst and can be used to carry additional postinst
#						  messages
# K_EXTRAEWARN			- same as K_EXTRAEINFO except ewarn's instead of einfo's
# K_SYMLINK				- if this is set, then forcably create symlink anyway

# H_SUPPORTEDARCH		- this should be a space separated list of ARCH's which
#						  can be supported by the headers ebuild

# UNIPATCH_LIST			- space delimetered list of patches to be applied to the
#						  kernel
# UNIPATCH_EXCLUDE		- an addition var to support exlusion based completely
#						  on "<passedstring>*" and not "<passedno#>_*"
#						- this should _NOT_ be used from the ebuild as this is
#						  reserved for end users passing excludes from the cli
# UNIPATCH_DOCS			- space delimemeted list of docs to be installed to
#						  the doc dir
# UNIPATCH_STRICTORDER	- if this is set places patches into directories of
#						  order, so they are applied in the order passed

inherit toolchain-funcs versionator multilib
ECLASS="kernel-2"
INHERITED="$INHERITED $ECLASS"
EXPORT_FUNCTIONS pkg_setup src_unpack src_compile src_install pkg_preinst pkg_postinst

export CTARGET=${CTARGET:-${CHOST}}
if [[ ${CTARGET} == ${CHOST} ]] ; then
	if [[ ${CATEGORY/cross-} != ${CATEGORY} ]] ; then
		export CTARGET=${CATEGORY/cross-}
	fi
fi

HOMEPAGE="http://www.kernel.org/ http://www.gentoo.org/"
LICENSE="GPL-2"

# set LINUX_HOSTCFLAGS if not already set
[ -z "$LINUX_HOSTCFLAGS" ] && LINUX_HOSTCFLAGS="-Wall -Wstrict-prototypes -Os -fomit-frame-pointer -I${S}/include"

#Eclass functions only from here onwards ...
#==============================================================
kernel_is() {
	# And lets add a sanity check
	[ -z "${KV_FULL}" ] && return 1	

        local RESULT operator test value i len
        RESULT=0

        operator="="
        if [ "${1}" == "lt" ]
        then
                operator="-lt"
                shift
        elif [ "${1}" == "gt" ]
        then
                operator="-gt"
                shift
        elif [ "${1}" == "le" ]
        then
                operator="-le"
                shift
        elif [ "${1}" == "ge" ]
        then
                operator="-ge"
                shift
        fi

        if [ -n "${1}" ]
        then
                value="${value}${1}"
                test="${test}${KV_MAJOR}"
        fi
        if [ -n "${2}" ]
        then
                len=$[ 3 - ${#2} ]
                for((i=0; i<$len; i++)); do
                        value="${value}0"
                done
                value="${value}${2}"

                len=$[ 3 - ${#KV_MINOR} ]
                for((i=0; i<$len; i++)); do
                        test="${test}0"
                done
                test="${test}${KV_MINOR}"
        fi
        if [ -n "${3}" ]
        then
                len=$[ 3 - ${#3} ]
                for((i=0; i<$len; i++)); do
                        value="${value}0"
                done
                value="${value}${3}"

                len=$[ 3 - ${#KV_PATCH} ]
                for((i=0; i<$len; i++)); do
                        test="${test}0"
                done
                test="${test}${KV_PATCH}"
        fi

        [ ${test} ${operator} ${value} ] && return 0 || return 1
}


kernel_is_2_4() {
	kernel_is 2 4
	return $?
}

kernel_is_2_6() {
	kernel_is 2 6 || kernel_is 2 5
	return $?
}

kernel_header_destdir() {
	[[ ${CTARGET} == ${CHOST} ]] \
		&& echo /usr/include \
		|| echo /usr/${CTARGET}/include
}

# Capture the sources type and set DEPENDs
if [ "${ETYPE}" == "sources" ]
then
	# binutils version needed to avoid Athlon/PIII/SSE assembler bugs.
	DEPEND="!build? ( sys-apps/sed
		>=sys-devel/binutils-2.11.90.0.31 )
		doc? ( !arm? ( !s390? ( app-text/docbook-sgml-utils ) ) )"

	RDEPEND="${DEPEND}
		!build? ( >=sys-libs/ncurses-5.2
		dev-lang/perl
		virtual/modutils
		sys-devel/make )"


	PROVIDE="virtual/linux-sources"
	kernel_is gt 2 4 && PROVIDE="${PROVIDE} virtual/alsa"
		
	SLOT="${PVR}"
	DESCRIPTION="Sources for the Linux kernel"
	IUSE="${IUSE} symlink build doc"
elif [ "${ETYPE}" == "headers" ]
then
	DESCRIPTION="Linux system headers"
	IUSE="${IUSE}"
	
	if [[ ${CTARGET} = ${CHOST} ]]
	then
		DEPEND="!virtual/os-headers"
		PROVIDE="virtual/kernel virtual/os-headers"
		SLOT="0"
	else
		SLOT="${CTARGET}"
	fi
else
	eerror "Unknown ETYPE=\"${ETYPE}\", must be \"sources\" or \"headers\""
	die
fi

# Unpack functions
#==============================================================
unpack_2_4() {
	cd ${S}
	# this file is required for other things to build properly,
	# so we autogenerate it
	make mrproper || die "make mrproper died"
	make include/linux/version.h || die "make include/linux/version.h failed"
	echo ">>> version.h compiled successfully."
}

universal_unpack() {
	[ -z "${OKV}" ] && OKV="${KV_MAJOR}.${KV_MINOR}.${KV_PATCH}"

	cd ${WORKDIR}
	unpack linux-${OKV}.tar.bz2
	if [ "${OKV}" != "${KV_FULL}" ]
	then
		mv linux-${OKV} linux-${KV_FULL} \
			|| die "Unable to move source tree to ${KV_FULL}."
	fi
	cd ${S}

	# change incorrect install path
	sed	-ie 's:#export\tINSTALL_PATH:export\tINSTALL_PATH:' Makefile

	# remove all backup files
	find . -iname "*~" -exec rm {} \; 2> /dev/null

	if [ -d "${S}/Documentation/DocBook" ]
	then
		cd ${S}/Documentation/DocBook
		sed -e "s:db2:docbook2:g" Makefile > Makefile.new \
			&& mv Makefile.new Makefile
		cd ${S}
	fi
	# fix a problem on ppc where TOUT writes to /usr/src/linux breaking sandbox
	use ppc && \
	sed -ie 's|TOUT	:= .tmp_gas_check|TOUT	:= $(T).tmp_gas_check|' \
	${S}/arch/ppc/Makefile
}

unpack_set_extraversion() {
	cd ${S}
	sed -ie "s:^\(EXTRAVERSION =\).*:\1 ${EXTRAVERSION}:" Makefile
}

# Compile Functions
#==============================================================
compile_headers() {
	# if we couldnt obtain HOSTCFLAGS from the Makefile, 
	# then set it to something sane
	local HOSTCFLAGS=$(getfilevar HOSTCFLAGS ${S}/Makefile)
	HOSTCFLAGS=${HOSTCFLAGS:--Wall -Wstrict-prototypes -O2 -fomit-frame-pointer}

	# Kernel ARCH != portage ARCH
	local KARCH=$(tc-arch-kernel ${CTARGET})

	# When cross-compiling, we need to set the ARCH/CROSS_COMPILE 
	# variables properly or bad things happen !
	local xmakeopts="ARCH=${KARCH}"
	if [[ ${CTARGET} != ${CHOST} ]] ; then
		xmakeopts="${xmakeopts} CROSS_COMPILE=${CTARGET}-"
	elif type -p ${CHOST}-ar ; then
		xmakeopts="${xmakeopts} CROSS_COMPILE=${CHOST}-"
	fi

	if kernel_is 2 4
	then
		yes "" | make oldconfig ${xmakeopts}
		echo ">>> make oldconfig complete"
		use sparc && make dep ${xmakeopts}

	elif kernel_is 2 6
	then
		# autoconf.h isnt generated unless it already exists. plus, we have
		# no guarantee that any headers are installed on the system...
		[[ -f ${ROOT}/usr/include/linux/autoconf.h ]] \
			|| touch include/linux/autoconf.h

		# if there arent any installed headers, then there also isnt an asm
		# symlink in /usr/include/, and make defconfig will fail, so we have
		# to force an include path with $S.
		HOSTCFLAGS="${HOSTCFLAGS} -I${S}/include/"
		ln -sf asm-${KARCH} "${S}"/include/asm
		make defconfig HOSTCFLAGS="${HOSTCFLAGS}" ${xmakeopts} || die "defconfig failed"
		make prepare HOSTCFLAGS="${HOSTCFLAGS}" ${xmakeopts} || die "prepare failed"
	fi
}

compile_manpages() {
	einfo "Making manpages ..."
	env -u ARCH make mandocs
}

# install functions
#==============================================================
install_universal() {
	#fix silly permissions in tarball
	cd ${WORKDIR}
	chown -R root:root *
	chmod -R a+r-w+X,u+w *
}

install_headers() {
	local ddir=$(kernel_header_destdir)

	cd ${S}
	dodir ${ddir}/linux
	cp -ax ${S}/include/linux/* ${D}/${ddir}/linux
	rm -rf ${D}/${ddir}/linux/modules
	dodir ${ddir}/asm

	if [ "${PROFILE_ARCH}" = "sparc64" -o "${PROFILE_ARCH}" = "sparc64-multilib" ] ; then
		rm -Rf ${D}/${ddir}/asm
		dodir ${ddir}/asm-sparc
		dodir ${ddir}/asm-sparc64
		cp -ax ${S}/include/asm-sparc/* ${D}/usr/include/asm-sparc
		cp -ax ${S}/include/asm-sparc64/* ${D}/usr/include/asm-sparc64
		#generate_sparc_asm ${D}/usr/include
		create_ml_includes /usr/include/asm __sparc__:/usr/include/asm-sparc __sparc64__:/usr/include/asm-sparc64
	elif [ "${ARCH}" = "amd64" ]; then
		rm -Rf ${D}/${ddir}/asm
		dodir ${ddir}/asm-i386
		dodir ${ddir}/asm-x86_64
		cp -ax ${S}/include/asm-i386/* ${D}/usr/include/asm-i386
		cp -ax ${S}/include/asm-x86_64/* ${D}/usr/include/asm-x86_64
		#/bin/sh ${FILESDIR}/generate-asm-amd64 ${D}/usr/include
		create_ml_includes /usr/include/asm __i386__:/usr/include/asm-i386 __x86_64__:/usr/include/asm-x86_64
	else
		cp -ax ${S}/include/asm/* ${D}/${ddir}/asm
	fi

	if kernel_is 2 6
	then
		dodir ${ddir}/asm-generic
		cp -ax ${S}/include/asm-generic/* ${D}/${ddir}/asm-generic
	fi
}

install_sources() {
	local doc
	local docs
	local file

	cd ${S}
	dodir /usr/src
	echo ">>> Copying sources ..."
	file="$(find ${WORKDIR} -iname "docs" -type d)"
	if [ -n "${file}" ]
	then
		for file in $(find ${file} -type f)
		do
			echo "${file/*docs\//}" >> ${S}/patches.txt
			echo "===================================================" >> ${S}/patches.txt
			cat ${file} >> ${S}/patches.txt
			echo "===================================================" >> ${S}/patches.txt
			echo "" >> ${S}/patches.txt
		done
	fi

	if [ ! -f ${S}/patches.txt ]
	then
		# patches.txt is empty so lets use our ChangeLog
		[ -f ${FILESDIR}/../ChangeLog ] && echo "Please check the ebuild ChangeLog for more details." > ${S}/patches.txt
	fi

	for doc in ${UNIPATCH_DOCS}
	do
		[ -f ${doc} ] && docs="${docs} ${doc}"
	done

	if [ -f ${S}/patches.txt ]; then
		docs="${docs} ${S}/patches.txt"
	fi

	if use doc && ! use arm && ! use s390; then
		install_manpages
	fi
	
	dodoc ${docs}
	mv ${WORKDIR}/linux* ${D}/usr/src
}

install_manpages() {
	env -u ARCH	sed -ie "s#/usr/local/man#${D}/usr/man#g" scripts/makeman
	ebegin "Installing manpages"
	env -u ARCH make installmandocs
	eend $?
	env -u ARCH sed -ie "s#${D}/usr/man#/usr/local/man#g" scripts/makeman
}

# pkg_preinst functions
#==============================================================
preinst_headers() {
	local ddir=$(kernel_header_destdir)
	[[ -L ${ddir}/linux ]] && rm ${ddir}/linux
	[[ -L ${ddir}/asm ]] && rm ${ddir}/asm
}

# pkg_postinst functions
#==============================================================
postinst_sources() {
	local MAKELINK=0
	
	# if we have USE=symlink, then force K_SYMLINK=1
	use symlink && K_SYMLINK=1

	# if we are to forcably symlink, delete it if it already exists first.
	if [[ -n ${K_SYMLINK} ]] ; then
		[[ -h ${ROOT}usr/src/linux ]] && rm ${ROOT}usr/src/linux
		MAKELINK=1
	fi
	
	# if the link doesnt exist, lets create it
	[[ ! -h ${ROOT}usr/src/linux ]] && MAKELINK=1
	
	[[ ${MAKELINK} == 1 ]] && \
		ln -sf ${ROOT}usr/src/linux-${KV_FULL} ${ROOT}usr/src/linux

	# Don't forget to make directory for sysfs
	[ ! -d "${ROOT}/sys" -a kernel_is_2_6 ] && mkdir /sys

	echo
	einfo "After installing a new kernel of any version, it is important"
	einfo "that you have the appropriate /etc/modules.autoload.d/kernel-X.Y"
	einfo "created (X.Y is the first 2 parts of your new kernel version)"
	echo
	einfo "For example, this kernel will require:"
	einfo "/etc/modules.autoload.d/kernel-${KV_MAJOR}.${KV_MINOR}"
	echo

	# if K_EXTRAEINFO is set then lets display it now
	if [[ -n ${K_EXTRAEINFO} ]] ; then
		echo ${K_EXTRAEINFO} | fmt |
		while read -s ELINE ; do
			einfo "${ELINE}"
		done

		echo
	fi

	# Show policy version, if this kernel has SELinux ...
	local secfile
	secfile="${ROOT}usr/src/linux-${KV_FULL}/security/selinux/include/security.h"
	if use selinux && [ -f "$secfile" ]
	then
		local polver=$(awk '/POLICYDB_VERSION /{print $3}' $secfile)
		einfo "The SELinux policy version of this kernel is $polver."
		echo
	fi

	# if K_EXTRAEWARN is set then lets display it now
	if [ -n "${K_EXTRAEWARN}" ]
	then
		echo ${K_EXTRAEWARN} | fmt |
		while read -s ELINE
		do
			ewarn "${ELINE}"
		done

		echo
	fi
}

postinst_headers() {
	einfo "Kernel headers are usually only used when recompiling glibc, as such, following the installation"
	einfo "of newer headers, it is advised that you re-merge glibc as follows:"
	einfo "emerge glibc"
	einfo "Failure to do so will cause glibc to not make use of newer features present in the updated kernel"
	einfo "headers."
}

# pkg_setup functions
#==============================================================
setup_headers() {
	[ -z "${H_SUPPORTEDARCH}" ] && H_SUPPORTEDARCH="${PN/-*/}"
	for i in ${H_SUPPORTEDARCH}
	do
		[ "${ARCH}" == "${i}" ] && H_ACCEPT_ARCH="yes"
	done

	if [ "${H_ACCEPT_ARCH}" != "yes" ]
	then
		echo
		eerror "This version of ${PN} does not support ${ARCH}."
		eerror "Please merge the appropriate sources, in most cases"
		eerror "(but not all) this will be called ${ARCH}-headers."
		die "Package unsupported for ${ARCH}"
	fi
}

# unipatch
#==============================================================
unipatch() {
	local i
	local x
	local extention
	local PIPE_CMD
	local UNIPATCH_DROP
	local KPATCH_DIR
	local PATCH_DEPTH
	local ELINE
	local STRICT_COUNT
	local PATCH_LEVEL
	local myLC_ALL
	
	# set to a standard locale to ensure sorts are ordered properly.
	myLC_ALL="${LC_ALL}"
	LC_ALL="C"

	[ -z "${KPATCH_DIR}" ] && KPATCH_DIR="${WORKDIR}/patches/"
	[ ! -d ${KPATCH_DIR} ] && mkdir -p ${KPATCH_DIR}

	# We're gonna need it when doing patches with a predefined patchlevel
	shopt -s extglob

	# This function will unpack all passed tarballs, add any passed patches, and remove any passed patchnumbers
	# usage can be either via an env var or by params
	# although due to the nature we pass this within this eclass
	# it shall be by param only.
	# -z "${UNIPATCH_LIST}" ] && UNIPATCH_LIST="${@}"
	UNIPATCH_LIST="${@}"

	#unpack any passed tarballs
	for i in ${UNIPATCH_LIST}
	do
		if [ -n "$(echo ${i} | grep -e "\.tar" -e "\.tbz" -e "\.tgz")" ]
		then
			extention=${i/*./}
			extention=${extention/:*/}
			case ${extention} in
				tbz2) PIPE_CMD="tar -xvjf";;
				 bz2) PIPE_CMD="tar -xvjf";;
				 tgz) PIPE_CMD="tar -xvzf";;
				  gz) PIPE_CMD="tar -xvzf";;
				   *) eerror "Unrecognized tarball compression"
				      die "Unrecognized tarball compression";;
			esac

			if [ -n "${UNIPATCH_STRICTORDER}" ]
			then
				STRICT_COUNT=$((${STRICT_COUNT} + 1))
				mkdir -p ${KPATCH_DIR}/${STRICT_COUNT}/
				${PIPE_CMD} ${i/:*/} -C ${KPATCH_DIR}/${STRICT_COUNT}/ 1>/dev/null
			else
				${PIPE_CMD} ${i/:*/} -C ${KPATCH_DIR} 1>/dev/null
			fi

			if [ $? == 0 ]
			then
				einfo "${i/*\//} unpacked"
				[ -n "$(echo ${i} | grep ':')" ] && echo ">>> Strict patch levels not currently supported for tarballed patchsets"
			else
				eerror "Failed to unpack ${i/:*/}"
				die "unable to unpack patch tarball"
			fi
		else
			extention=${i/*./}
			extention=${extention/:*/}
			PIPE_CMD=""
			case ${extention} in
				    bz2) PIPE_CMD="bzip2 -dc";;
				  patch) PIPE_CMD="cat";;
				   diff) PIPE_CMD="cat";;
				 gz|Z|z) PIPE_CMD="gzip -dc";;
				ZIP|zip) PIPE_CMD="unzip -p";;
				      *) UNIPATCH_DROP="${UNIPATCH_DROP} ${i/:*/}";;
			esac

			PATCH_LEVEL=${i/*([^:])?(:)}
			i=${i/:*/}
			x=${i/*\//}
			x=${x/\.${extention}/}

			if [ -n "${PIPE_CMD}" ]
			then
				if [ ! -r "${i}" ]
				then
					echo
					eerror "FATAL: unable to locate:"
					eerror "${i}"
					eerror "for read-only. The file either has incorrect permissions"
					eerror "or does not exist."
					die Unable to locate ${i}
				fi

				if [ -n "${UNIPATCH_STRICTORDER}" ]
				then
					STRICT_COUNT=$((${STRICT_COUNT} + 1))
					mkdir -p ${KPATCH_DIR}/${STRICT_COUNT}/
					$(${PIPE_CMD} ${i} > ${KPATCH_DIR}/${STRICT_COUNT}/${x}.patch${PATCH_LEVEL})
				else
					$(${PIPE_CMD} ${i} > ${KPATCH_DIR}/${x}.patch${PATCH_LEVEL})
				fi
			fi
		fi
	done

	#populate KPATCH_DIRS so we know where to look to remove the excludes
	x=${KPATCH_DIR}
	KPATCH_DIR=""
	for i in $(find ${x} -type d | sort -n)
	do
		KPATCH_DIR="${KPATCH_DIR} ${i}"
	done

	#so now lets get rid of the patchno's we want to exclude
	UNIPATCH_DROP="${UNIPATCH_EXCLUDE} ${UNIPATCH_DROP}"
	for i in ${UNIPATCH_DROP}
	do
		ebegin "Excluding Patch #${i}"
		for x in ${KPATCH_DIR}
		do
			rm -f ${x}/${i}* 2>/dev/null
		done
		eend $?
	done

	# and now, finally, we patch it :)
	for x in ${KPATCH_DIR}
	do
		for i in $(find ${x} -maxdepth 1 -iname "*.patch*" -or -iname "*.diff*" | sort -n)
		do
			STDERR_T="${T}/${i/*\//}"
			STDERR_T="${STDERR_T/.patch*/.err}"

			[ -z ${i/*.patch*/} ] && PATCH_DEPTH=${i/*.patch/}
			[ -z ${i/*.diff*/} ]  && PATCH_DEPTH=${i/*.diff/}

			if [ -z "${PATCH_DEPTH}" ]; then
				PATCH_DEPTH=0
			fi

			ebegin "Applying ${i/*\//} (-p${PATCH_DEPTH}+)"
			while [ ${PATCH_DEPTH} -lt 5 ]
			do
				echo "Attempting Dry-run:" >> ${STDERR_T}
				echo "cmd: patch -p${PATCH_DEPTH} --dry-run -f < ${i}" >> ${STDERR_T}
				echo "=======================================================" >> ${STDERR_T}
				if [ $(patch -p${PATCH_DEPTH} --dry-run -f < ${i} >> ${STDERR_T}) $? -eq 0 ]
				then
					echo "Attempting patch:" > ${STDERR_T}
					echo "cmd: patch -p${PATCH_DEPTH} -f < ${i}" >> ${STDERR_T}
					echo "=======================================================" >> ${STDERR_T}
					if [ $(patch -p${PATCH_DEPTH} -f < ${i} >> ${STDERR_T}) "$?" -eq 0 ]
					then
						eend 0
						rm ${STDERR_T}
						break
					else
						eend 1
						eerror "Failed to apply patch ${i/*\//}"
						eerror "Please attach ${STDERR_T} to any bug you may post."
						die "Failed to apply ${i/*\//}"
					fi
				else
					PATCH_DEPTH=$((${PATCH_DEPTH} + 1))
				fi
			done
			if [ ${PATCH_DEPTH} -eq 5 ]
			then
				eend 1
				eerror "Please attach ${STDERR_T} to any bug you may post."
				die "Unable to dry-run patch."
			fi
		done
	done

	# clean up  KPATCH_DIR's - fixes bug #53610
	for x in ${KPATCH_DIR}
	do
		rm -Rf ${x}
	done
	
	LC_ALL="${myLC_ALL}"
}

# getfilevar accepts 2 vars as follows:
# getfilevar <VARIABLE> <CONFIGFILE>
# pulled from linux-info

getfilevar() {
local	ERROR workingdir basefname basedname xarch
	ERROR=0

	[ -z "${1}" ] && ERROR=1
	[ ! -f "${2}" ] && ERROR=1

	if [ "${ERROR}" = 1 ]
	then
		ebeep
		echo -e "\n"
		eerror "getfilevar requires 2 variables, with the second a valid file."
		eerror "   getfilevar <VARIABLE> <CONFIGFILE>"
	else
		workingdir=${PWD}
		basefname=$(basename ${2})
		basedname=$(dirname ${2})
		xarch=${ARCH}
		unset ARCH
		
		cd ${basedname}
		echo -e "include ${basefname}\ne:\n\t@echo \$(${1})" | \
			make ${BUILD_FIXES} -f - e 2>/dev/null
		cd ${workingdir}
		 
		ARCH=${xarch}
	fi
}

detect_version() {
	# this function will detect and set
	# - OKV: Original Kernel Version (2.6.0/2.6.0-test11)
	# - KV: Kernel Version (2.6.0-gentoo/2.6.0-test11-gentoo-r1)
	# - EXTRAVERSION: The additional version appended to OKV (-gentoo/-gentoo-r1)

	if [ -n "${KV_FULL}" ] ;
	then
		# we will set this for backwards compatibility.
		KV=${KV_FULL}

		# we know KV_FULL so lets stop here. but not without resetting S
		S=${WORKDIR}/linux-${KV_FULL}
		return
	fi

	if [ -z "${OKV}" ]
	then
		OKV=${PV/_beta/-test}
		OKV=${OKV/_rc/-rc}
		OKV=${OKV/_p*/}
		OKV=${OKV/-r*/}
	fi

	KV_MAJOR=$(get_version_component_range 1 ${OKV})
	KV_MINOR=$(get_version_component_range 2 ${OKV})
	KV_PATCH=$(get_version_component_range 3- ${OKV})
	KV_PATCH=${KV_PATCH/[-_]*/}

	KERNEL_URI="mirror://kernel/linux/kernel/v${KV_MAJOR}.${KV_MINOR}/linux-${OKV}.tar.bz2"

	RELEASE=${PV/${OKV}/}
	RELEASE=${RELEASE/_beta/}
	RELEASE=${RELEASE/_rc/-rc}
	if [ $(kernel_is_2_4) $? == 0 ]
	then
		RELEASE=${RELEASE/_pre/-pre}
	else
		RELEASE=${RELEASE/_pre/-bk}
	fi
	RELEASETYPE=${RELEASE//[0-9]/}
	EXTRAVERSION="${RELEASE}"

	if [ -n "${K_PREPATCHED}" ]
	then
		EXTRAVERSION="${EXTRAVERSION}-${PN/-*/}${PR/r/}"
	elif [ ${ETYPE} != "headers" ]
	then
		[ -z "${K_NOUSENAME}" ] && EXTRAVERSION="${EXTRAVERSION}-${PN/-*/}"
		[ "${PN/-*/}" == "wolk" ] && EXTRAVERSION="-${PN/-*/}-${PV}"
		[ "${PN/-*/}" == "vserver" ] && EXTRAVERSION="-${PN/-*/}-${PV}"
		[ "${PR}" != "r0" ] 	&& EXTRAVERSION="${EXTRAVERSION}-${PR}"
	fi

	KV_FULL=${OKV}${EXTRAVERSION}

	# -rcXX-bkXX pulls are *IMPOSSIBLE* to support within the portage naming convention
	# these cannot be supported, but the code here can handle it up until this point
	# and theoretically thereafter.

	if [ "${RELEASETYPE}" == "-rc" -o "${RELEASETYPE}" == "-pre" ]
	then
		OKV="${KV_MAJOR}.${KV_MINOR}.$([ $((${KV_PATCH} - 1)) -lt 0 ] && echo ${KV_PATCH} || echo $((${KV_PATCH} - 1)))"
		KERNEL_URI="mirror://kernel/linux/kernel/v${KV_MAJOR}.${KV_MINOR}/testing/patch-${PV//_/-}.bz2
			    mirror://kernel/linux/kernel/v${KV_MAJOR}.${KV_MINOR}/linux-${OKV}.tar.bz2"
		UNIPATCH_LIST_DEFAULT="${DISTDIR}/patch-${PV//_/-}.bz2"
		KV_FULL=${PV/[-_]*/}${EXTRAVERSION}
	fi

	if [ "${RELEASETYPE}" == "-bk" ]
	then
		OKV="${KV_MAJOR}.${KV_MINOR}.${KV_PATCH}"
		KERNEL_URI="mirror://kernel/linux/kernel/v${KV_MAJOR}.${KV_MINOR}/snapshots/patch-${KV_MAJOR}.${KV_MINOR}.${KV_PATCH}${RELEASE}.bz2
			    mirror://kernel/linux/kernel/v${KV_MAJOR}.${KV_MINOR}/linux-${OKV}.tar.bz2"
		UNIPATCH_LIST_DEFAULT="${DISTDIR}/patch-${KV_MAJOR}.${KV_MINOR}.${KV_PATCH}${RELEASE}.bz2"
		KV_FULL=${PV/[-_]*/}${EXTRAVERSION}
	fi

	if [ "${RELEASETYPE}" == "-rc-bk" ]
	then
		OKV="${KV_MAJOR}.${KV_MINOR}.$((${KV_PATCH} - 1))-${RELEASE/-bk*}"
		EXTRAVERSION="$([ -n "${RELEASE}" ] && echo ${RELEASE/*-bk/-bk})$([ -n "${K_USENAME}" ] && echo -${PN/-*/})$([ ! "${PR}" == "r0" ] && echo -${PR})"

		KERNEL_URI="mirror://kernel/linux/kernel/v${KV_MAJOR}.${KV_MINOR}/snapshots/patch-${KV_MAJOR}.${KV_MINOR}.${KV_PATCH}${RELEASE}.bz2
			    mirror://kernel/linux/kernel/v${KV_MAJOR}.${KV_MINOR}/linux-${OKV}.tar.bz2"
		UNIPATCH_LIST_DEFAULT="${DISTDIR}/patch-${KV_MAJOR}.${KV_MINOR}.${KV_PATCH}${RELEASE}.bz2"
		KV_FULL=${PV/[-_]*/}${EXTRAVERSION}
	fi

	S=${WORKDIR}/linux-${KV_FULL}
	# we will set this for backwards compatibility.
	KV=${KV_FULL}
}

detect_arch() {
	# This function sets ARCH_URI and ARCH_PATCH
	# with the neccessary info for the arch sepecific compatibility
	# patchsets.

	local ALL_ARCH
	local LOOP_ARCH
	local COMPAT_URI
	local i

	# COMPAT_URI is the contents of ${ARCH}_URI
	# ARCH_URI is the URI for all the ${ARCH}_URI patches
	# ARCH_PATCH is ARCH_URI broken into files for UNIPATCH

	ARCH_URI=""
	ARCH_PATCH=""
	ALL_ARCH="X86 PPC PPC64 SPARC MIPS ALPHA ARM HPPA AMD64 IA64 X86OBSD S390"

	for LOOP_ARCH in ${ALL_ARCH}
	do
		COMPAT_URI="${LOOP_ARCH}_URI"
		COMPAT_URI="${!COMPAT_URI}"

		[ -n "${COMPAT_URI}" ] && \
			ARCH_URI="${ARCH_URI} $(echo ${LOOP_ARCH} | tr '[:upper:]' '[:lower:]')? ( ${COMPAT_URI} )"

		if [ "${LOOP_ARCH}" == "$(echo ${ARCH} | tr '[:lower:]' '[:upper:]')" ]
		then
			for i in ${COMPAT_URI}
			do
				ARCH_PATCH="${ARCH_PATCH} ${DISTDIR}/${i/*\//}"
			done
		fi
	done
}

# sparc nastiness
#==============================================================
# This script generates the files in /usr/include/asm for sparc systems
# during installation of sys-kernel/linux-headers.
# Will no longer be needed when full 64 bit support is used on sparc64
# systems.
#
# Shamefully ripped from Debian
# ----------------------------------------------------------------------

# Idea borrowed from RedHat's kernel package

# This is gonna get replaced by something in multilib.eclass soon...
# --eradicator
generate_sparc_asm() {
	local name

	cd $1 || die
	mkdir asm

	for h in `( ls asm-sparc; ls asm-sparc64 ) | grep '\.h$' | sort -u`; do
		name="$(echo $h | tr a-z. A-Z_)"
		# common header
		echo "/* All asm/ files are generated and point to the corresponding
 * file in asm-sparc or asm-sparc64.
 */

#ifndef __SPARCSTUB__${name}__
#define __SPARCSTUB__${name}__
" > asm/${h}

		# common for sparc and sparc64
		if [ -f asm-sparc/$h -a -f asm-sparc64/$h ]; then
			echo "#ifdef __arch64__
#include <asm-sparc64/$h>
#else
#include <asm-sparc/$h>
#endif
" >> asm/${h}

		# sparc only
		elif [ -f asm-sparc/$h ]; then
echo "#ifndef __arch64__
#include <asm-sparc/$h>
#endif
" >> asm/${h}

		# sparc64 only
		else
echo "#ifdef __arch64__
#include <asm-sparc64/$h>
#endif
" >> asm/${h}
		fi

		# common footer
		echo "#endif /* !__SPARCSTUB__${name}__ */" >> asm/${h}
	done
	return 0
}

headers___fix() {
	sed -i \
		-e "s/\([ "$'\t'"]\)u8\([ "$'\t'"]\)/\1__u8\2/g;" \
		-e "s/\([ "$'\t'"]\)u16\([ "$'\t'"]\)/\1__u16\2/g;" \
		-e "s/\([ "$'\t'"]\)u32\([ "$'\t'"]\)/\1__u32\2/g;" \
		-e "s/\([ "$'\t'"]\)u64\([ "$'\t'"]\)/\1__u64\2/g;" \
		"$@"
}

# common functions
#==============================================================
kernel-2_src_unpack() {
	detect_version
	universal_unpack

	[ -n "${UNIPATCH_LIST}" -o -n "${UNIPATCH_LIST_DEFAULT}" ] && \
		unipatch "${UNIPATCH_LIST_DEFAULT} ${UNIPATCH_LIST}"

	[ -z "${K_NOSETEXTRAVERSION}" ] && \
		unpack_set_extraversion

	kernel_is 2 4 && unpack_2_4
}

kernel-2_src_compile() {
	cd ${S}
	[ "${ETYPE}" == "headers" ] && compile_headers
	[ "${ETYPE}" == "sources" ] && \
		use doc && ! use arm && ! use s390 && compile_manpages
}

kernel-2_pkg_preinst() {
	[ "${ETYPE}" == "headers" ] && preinst_headers
}

kernel-2_src_install() {
	install_universal
	[ "${ETYPE}" == "headers" ] && install_headers
	[ "${ETYPE}" == "sources" ] && install_sources
}

kernel-2_pkg_postinst() {
	[ "${ETYPE}" == "headers" ] && postinst_headers
	[ "${ETYPE}" == "sources" ] && postinst_sources
}

kernel-2_pkg_setup() {
	[ "${ETYPE}" == "headers" ] && setup_headers

	# This is to fix some weird portage bug? in stable versions of portage.
	[ "${ETYPE}" == "sources" ] && echo ">>> Preparing to unpack ..."
}