# Copyright 1999-2003 Gentoo Technologies, Inc.
# Distributed under the terms of the GNU General Public License v2
# $Header: 

IUSE="build pcmcia xfs acpi grsec aavm rmap"

ETYPE="sources"
inherit kernel || die

# OKV=original kernel version, KV=patched kernel version.
OKV="2.4.21"
KV="2.4.21-ck${PR/r/}"
S=${WORKDIR}/linux-${KV}
EXTRAVERSION="-ck${PR/r/}"

DESCRIPTION="Full sources for the Con Kolivas's high performance kernel and its optional features"
HOMEPAGE="http://members.optusnet.com.au/ckolivas/kernel"

### Below is a list of all the available patches:

## Performance enhancements (installed by default):
# Base ck patch (contains the batch O(1) scheduler, preemptible,
# low latency, and interactivity):
# (added by default)
BASE_PATCH="patch-1000_O1_PE_LL_0306300059_2.4.21-ck3.bz2"
# Con Colivas autoregulation vm hacks:
# USE: -aavm -rmap
CKVM_PATCH="patch-1010_CKVM_0306300027_2.4.21-ck3.bz2"
# Swap prefetching:
# USE: -aavm -rmap
SP_PATCH="patch-1011_SP_0306102217_2.4.21-ck2.bz2"
# Read Latency2:
# (added by default)
RL2="patch-1020_RL2_0305310042_2.4.21-ck2.bz2"
# Desktop Tuning 1:
# (added by default)
DT1_PATCH="patch-1021_DT1_030531616_2.4.21-ck2.bz2"
# Variable HZ setting:
# USE: -pcmcia
VH_PATCH="patch-1030_VH_0306200116_2.4.21-ck2.bz2"
# Desktop Tuning 2:
# USE: -pcmcia
DT2_PATCH="patch-1031_DT2_0306200119_2.4.21-ck2.bz2"
# Scheduler Tunables:
# (added by default)
ST_PATCH="patch-1040_ST_0306230135_2.4.21-ck2.bz2"

## Extra features:
# Supermount-NG v1.2.7:
# (added by default)
SM_PATCH="patch-1050_SM1.2.7_0306201731_2.4.21-ck2.patch.bz2"
# XFS file system:
# USE: xfs
XFS_PATCH="patch-1060_XFS1.3.0pre2_0306201757_2.4.21-ck2.bz2"
# ACPI 20030522:
# USE: acpi
ACPI_PATCH="patch-1070_ACPI_0306300010_2.4.21-ck3.bz2"
# Bootsplash:
# (added by default)
BS_PATCH="patch-1090_BS_0306020027_2.4.21-ck2.bz2"

## Misc other patches:
# Nvidia Nforce2 update:
# (added by default)
NF2_PATCH="patch-1080_NF2_0305311048_2.4.21-ck2.bz2"
# CPU Frequency scaling for supported laptops:
# USE: pcmcia
CFS_PATCH="1100_CFS_0306161356_2.4.21-ck1.patch.bz2"
# Grsec 1.9.9h (currently depends on CKVM and XFS): 
# USE: grsec -rmap -aavm
GRS_PATCH="patch-1161_GRS1.9.9h_0306230051_2.4.21-ck2.bz2"
# Packet writing for CDRW/DVDR
# (added by default)
PW_PATCH="patch-1100_PW_0306221328_2.4.21-ck2.bz2"

## Alternative VMs:
# AAVM: 
# USE: aavm -rmap 
AAVM_PATCH="1010_AAVM_0306191118_2.4.21-ck1.patch.bz2"
# Rmap:
# USE: rmap -aavm
RMAP_PATCH="1010_rmap15j_0306172008_2.4.21-ck1.patch.bz2"


### Create the SRC_URI from USE flags.
#CK_URL="http://members.optusnet.com.au/ckolivas/kernel"
TGL_URL="http://tdegreni.free.fr/ck-sources"
CK_URL="${TGL_URL}"
SRC_URI="http://www.kernel.org/pub/linux/kernel/v2.4/linux-${OKV}.tar.bz2 \
		${CK_URL}/${BASE_PATCH} \
		${CK_URL}/${CKVM_PATCH} \
		${CK_URL}/${SP_PATCH} \
		${CK_URL}/${RL2} \
		${CK_URL}/${DT1_PATCH} \
		${CK_URL}/${VH_PATCH} \
		${CK_URL}/${DT2_PATCH} \
		${CK_URL}/${ST_PATCH} \
		${CK_URL}/${SM_PATCH} \
		xfs? ( ${CK_URL}/${XFS_PATCH} ) \
		acpi? ( ${CK_URL}/${ACPI_PATCH} ) \
		${CK_URL}/${NF2_PATCH} \
		${CK_URL}/${BS_PATCH} \
		pcmcia? ( ${CK_URL}/${CFS_PATCH} ) \
		${CK_URL}/${PW_PATCH} \
		rmap? ( ${CK_URL}/${RMAP_PATCH} ) \
		aavm? ( ${CK_URL}/${AAVM_PATCH} ) \
		grsec? ( ${CK_URL}/${XFS_PATCH} ) \
		grsec? ( ${CK_URL}/${GRS_PATCH} )"

KEYWORDS="~x86 -ppc"
SLOT="${KV}"

## Utility functions

add_patches() {
	for PATCH in $*
	do
		if [ ! -L ${PATCH#patch-} ]; then
			ln -s ${DISTDIR}/${PATCH} ${PATCH#patch-} || die "Can't add patch ${PATCH}"
		fi
	done
}

rem_patches() {
	for PATCH in $*
	do
		if [ -L ${PATCH#patch-} ]; then
			 rm ${PATCH#patch-} || die "Can't remove patch ${PATCH}"
		fi
	done
}

apply_patches() {
	cd linux-${OKV}
	for PATCH in ../1*
	do
		einfo "Apply patch ${PATCH#\.\.\/}"
		bzcat ${PATCH} | patch -p1 -s || die "Patching with ${PATCH#\.\.\/} failed."
	done
	cd ..
}

## End of the utility functions

src_unpack() {

	# Check for conflicts without obvious default choice:
	[ -n "`use rmap`" -a -n "`use aavm`" ] && \
	  die "You'll have to choose between AAVM and Rmap."
	[ -n "`use grsec`" ] && [ -n "`use rmap`" -o -n "`use aavm`" ] && \
	  die "Grsecurity patch currently won't work with AAVM or Rmap."

	# Unpack the vanilla sources
	unpack linux-${OKV}.tar.bz2

	# Add the main separate patches:
	add_patches ${BASE_PATCH} ${CKVM_PATCH} ${SP_PATCH} ${RL2} ${DT1_PATCH} ${ST_PATCH} ${VH_PATCH} ${DT2_PATCH}
	[ -n "`use pcmcia`" ] && \
	  einfo "PCMCIA is in use: \"Variable HZ setting\" and \"Desktop Tuning 2\" removed." && \
	  rem_patches ${VH_PATCH} ${DT2_PATCH}
	
	# Add optional features:
	add_patches ${SM_PATCH} ${NF2_PATCH} ${BS_PATCH} ${PW_PATCH}
	[ -n "`use xfs`" ] && add_patches ${XFS_PATCH}
	[ -n "`use acpi`" ] && add_patches ${ACPI_PATCH}
	[ -n "`use rmap`" -o -n "`use aavm`" ] && \
	  einfo "A non-CK VM is in use." && \
	  rem_patches ${SP_PATCH} ${CKVM_PATCH}
	[ -n "`use pcmcia`" ] && add_patches ${CFS_PATCH}
	[ -n "`use grsec`" ] && add_patches ${GRS_PATCH}
	[ -n "`use grsec`" -a ! -n "`use xfs`" ] && \
	  einfo "Grsec is in use: XFS added." && \
	  add_patches ${XFS_PATCH}
	[ -n "`use rmap`" ] && add_patches ${RMAP_PATCH}
	[ -n "`use aavm`" ] && add_patches ${AAVM_PATCH}
	
	# Apply the selected patches
	apply_patches

	# Rename the kernel
	mv linux-${OKV} linux-${KV} || die
	
	# Do the usual cleanups
	cd linux-${KV}
	kernel_universal_unpack
}

pkg_postinst() {

	# Create the /usr/src/linux link if needed
	kernel_pkg_postinst

	# Display some configuration advices:
	echo
	[ -n "`use xfs`" -o -n "`use grsec`" ] && einfo "It is safer to disable \"Preempt\" if you use XFS."
	echo
	einfo "Do NOT use hdparm with this 2.4.21 kernel. It will timeout,"
	einfo "not set dma properly and can cause fs corruption if you use"
	einfo "it during hd activity!"
	echo
}